Headline
Ransomware Hackers Using New Way to Bypass MS Exchange ProxyNotShell Mitigations
Threat actors affiliated with a ransomware strain known as Play are leveraging a never-before-seen exploit chain that bypasses blocking rules for ProxyNotShell flaws in Microsoft Exchange Server to achieve remote code execution (RCE) through Outlook Web Access (OWA). “The new exploit method bypasses URL rewrite mitigations for the Autodiscover endpoint,” CrowdStrike researchers Brian Pitchford,
Email Security / Data Security
Threat actors affiliated with a ransomware strain known as Play are leveraging a never-before-seen exploit chain that bypasses blocking rules for ProxyNotShell flaws in Microsoft Exchange Server to achieve remote code execution (RCE) through Outlook Web Access (OWA).
“The new exploit method bypasses URL rewrite mitigations for the Autodiscover endpoint,” CrowdStrike researchers Brian Pitchford, Erik Iker, and Nicolas Zilio said in a technical write-up published Tuesday.
Play ransomware, which first surfaced in June 2022, has been revealed to adopt many tactics employed by other ransomware families such as Hive and Nokoyawa, the latter of which upgraded to Rust in September 2022.
The cybersecurity company’s investigations into several Play ransomware intrusions found that initial access to the target environments was not achieved by directly exploiting CVE-2022-41040, but rather through the OWA endpoint.
Dubbed OWASSRF, the technique likely takes advantage of another critical flaw tracked as CVE-2022-41080 (CVSS score: 8.8) to achieve privilege escalation, followed by abusing CVE-2022-41082 for remote code execution.
It’s worth noting that both CVE-2022-41040 and CVE-2022-41080 stem from a case of server-side request forgery (SSRF), which permits an attacker to access unauthorized internal resources, in this case the PowerShell remoting service.
CrowdStrike said the successful initial access enabled the adversary to drop legitimate Plink and AnyDesk executables to maintain persistent access as well as take steps to purge Windows Event Logs on infected servers to conceal the malicious activity.
All three vulnerabilities were addressed by Microsoft as part of its Patch Tuesday updates for November 2022. It’s, however, unclear if CVE-2022-41080 was actively exploited as a zero-day alongside CVE-2022-41040 and CVE-2022-41082.
The Windows maker, for its part, has tagged CVE-2022-41080 with an “Exploitation More Likely” assessment, implying it’s possible for an attacker to create exploit code that could be utilized to reliably weaponize the flaw.
CrowdStrike further noted that a proof-of-concept (PoC) Python script discovered and leaked by Huntress Labs researcher Dray Agha last week may have been put to use by the Play ransomware actors for initial access.
This is evidenced by the fact that the execution of the Python script made it possible to “replicate the logs generated in recent Play ransomware attacks.”
“Organizations should apply the November 8, 2022 patches for Exchange to prevent exploitation since the URL rewrite mitigations for ProxyNotShell are not effective against this exploit method,” the researchers said.
Found this article interesting? Follow us on Twitter and LinkedIn to read more exclusive content we post.
Related news
The threat actors behind the Play ransomware are estimated to have impacted approximately 300 entities as of October 2023, according to a new joint cybersecurity advisory from Australia and the U.S. "Play ransomware actors employ a double-extortion model, encrypting systems after exfiltrating data and have impacted a wide range of businesses and critical infrastructure organizations in North
A predictable patch cadence is nice, but the software giant can do more.
Categories: Threat Intelligence Our Threat Intelligence team looks at known ransomware attacks by gang, country, and industry sector in December 2022, and looks at why LockBit had to make a public apology (Read more...) The post Ransomware in December 2022 appeared first on Malwarebytes Labs.
By Waqas Cybercriminals are leveraging two exploit chains (ProxyNotShell/OWASSRF) to target Microsoft Exchange servers, as warned by Bitdefender Labs. This is a post from HackRead.com Read the original post: New Wave of Cyberattacks Targeting MS Exchange Servers
The first Patch Tuesday fixes shipped by Microsoft for 2023 have addressed a total of 98 security flaws, including one bug that the company said is being actively exploited in the wild. 11 of the 98 issues are rated Critical and 87 are rated Important in severity, with the vulnerabilities also listed as publicly known at the time of release. Separately, the Windows maker is expected to release
Organizations often defer patching because of business disruption fears — but that didn't work out very well for Rackspace's Hosted Exchange service.
Cloud services provider Rackspace on Thursday confirmed that the ransomware gang known as Play was responsible for last month's breach. The security incident, which took place on December 2, 2022, leveraged a previously unknown security exploit to gain initial access to the Rackspace Hosted Exchange email environment. "This zero-day exploit is associated with CVE-2022-41080," the Texas-based
The hosting services provider shared new details on the breach that took down its Hosted Exchange Email service.
The hosting provider had not applied Microsoft's new patch due to publicly reported issues with the update.
The Play ransomware group was spotted exploiting another little-known SSRF bug to trigger RCE on affected Exchange servers.
This Metasploit module chains two vulnerabilities on Microsoft Exchange Server that, when combined, allow an authenticated attacker to interact with the Exchange Powershell backend (CVE-2022-41040), where a deserialization flaw can be leveraged to obtain code execution (CVE-2022-41082). This exploit only supports Exchange Server 2019. These vulnerabilities were patched in November 2022.
This Metasploit module chains two vulnerabilities on Microsoft Exchange Server that, when combined, allow an authenticated attacker to interact with the Exchange Powershell backend (CVE-2022-41040), where a deserialization flaw can be leveraged to obtain code execution (CVE-2022-41082). This exploit only supports Exchange Server 2019. These vulnerabilities were patched in November 2022.
Hello everyone! This episode will be about Microsoft Patch Tuesday for November 2022, including vulnerabilities that were added between October and November Patch Tuesdays. As usual, I use my open source Vulristics project to create the report. Alternative video link (for Russia): https://vk.com/video-149273431_456239107 The most important news of this Patch Tuesday was a release of patches […]
Microsoft Exchange Server Elevation of Privilege Vulnerability. This CVE ID is unique from CVE-2022-41123.
Microsoft Exchange Server Elevation of Privilege Vulnerability
By Deeba Ahmed Microsoft has urged Windows Administrators to install the updates urgently so make sure you have the latest patches installed! This is a post from HackRead.com Read the original post: Microsoft Issues Patches to Fix 6 Active 0-Day Windows Vulnerabilities
Microsoft's latest round of monthly security updates has been released with fixes for 68 vulnerabilities spanning its software portfolio, including patches for six actively exploited zero-days. 12 of the issues are rated Critical, two are rated High, and 55 are rated Important in severity. This also includes the weaknesses that were closed out by OpenSSL the previous week. Also separately
Let's face it: Having “2022 election” in the headline above is probably the only reason anyone might read this story today. Still, while most of us here in the United States are anxiously awaiting the results of how well we've patched our Democracy, it seems fitting that Microsoft Corp. today released gobs of security patches for its ubiquitous Windows operating systems. November's patch batch includes fixes for a whopping six zero-day security vulnerabilities that miscreants and malware are already exploiting in the wild.
Microsoft released its monthly security update on Tuesday, disclosing 62 vulnerabilities. Of these vulnerabilities, 8 are classified as “Critical” and the rest are classified as “Important.”
Microsoft on Friday disclosed it has made more improvements to the mitigation method offered as a means to prevent exploitation attempts against the newly disclosed unpatched security flaws in Exchange Server. To that end, the tech giant has revised the blocking rule in IIS Manager from ".*autodiscover\.json.*Powershell.*" to "(?=.*autodiscover\.json)(?=.*powershell)." The list of
Microsoft on Friday disclosed it has made more improvements to the mitigation method offered as a means to prevent exploitation attempts against the newly disclosed unpatched security flaws in Exchange Server. To that end, the tech giant has revised the blocking rule in IIS Manager from ".*autodiscover\.json.*Powershell.*" to "(?=.*autodiscover\.json)(?=.*powershell)." The list of
By Jon Munshaw. Welcome to this week’s edition of the Threat Source newsletter. As I wrote about last week, I’ve been diving a lot into apps’ privacy policies recently. And I was recently made aware of a new type of app I never knew existed — family trackers. There are countless mobile apps for parents to track their children or other family members based on their location, phone usage, and even driving speed. As an anxious soon-to-be-parent, this sounds intriguing to me — it’d be a supped-up version of Find my Friends on Apple devices so I’d never have to ask my teenager (granted, I’m many years away from being at that stage of my life) when they were coming home or where they were. Just as with all other types of mobile apps, there are pitfalls, though. Life360, one of the most popular of these types of apps and even tells users what their maximum driving speed was on a given trip, was found in December 2021 to be selling precise location data on its users, potentia...
By Jon Munshaw. Welcome to this week’s edition of the Threat Source newsletter. As I wrote about last week, I’ve been diving a lot into apps’ privacy policies recently. And I was recently made aware of a new type of app I never knew existed — family trackers. There are countless mobile apps for parents to track their children or other family members based on their location, phone usage, and even driving speed. As an anxious soon-to-be-parent, this sounds intriguing to me — it’d be a supped-up version of Find my Friends on Apple devices so I’d never have to ask my teenager (granted, I’m many years away from being at that stage of my life) when they were coming home or where they were. Just as with all other types of mobile apps, there are pitfalls, though. Life360, one of the most popular of these types of apps and even tells users what their maximum driving speed was on a given trip, was found in December 2021 to be selling precise location data on its users, potentia...
Microsoft Exchange Server Elevation of Privilege Vulnerability.
Microsoft Exchange Server Remote Code Execution Vulnerability.
Microsoft on Friday disclosed that a single activity group in August 2022 achieved initial access and breached Exchange servers by chaining the two newly disclosed zero-day flaws in a limited set of attacks aimed at less than 10 organizations globally. "These attacks installed the Chopper web shell to facilitate hands-on-keyboard access, which the attackers used to perform Active Directory
Microsoft on Friday disclosed that a single activity group in August 2022 achieved initial access and breached Exchange servers by chaining the two newly disclosed zero-day flaws in a limited set of attacks aimed at less than 10 organizations globally. "These attacks installed the Chopper web shell to facilitate hands-on-keyboard access, which the attackers used to perform Active Directory
While organizations wait for an official patch for the two zero-day flaws in Microsoft Exchange, they should scan their networks for signs of exploitation and apply these mitigations.
While organizations wait for an official patch for the two zero-day flaws in Microsoft Exchange, they should scan their networks for signs of exploitation and apply these mitigations.
Cisco Talos has released new coverage to detect and prevent the exploitation of two recently disclosed vulnerabilities collectively referred to as "ProxyNotShell," affecting Microsoft Exchange Servers 2013, 2016 and 2019. One of these vulnerabilities could allow an attacker to execute remote code on the targeted server. Limited exploitation of these vulnerabilities in the wild has been reported. CVE-2022-41040 is a Server Side Request Forgery (SSRF) vulnerability, while CVE-2022-41082 enables Remote Code Execution (RCE) when PowerShell is accessible to the attackers. While no fixes or patches are available yet, Microsoft has provided mitigations for on-premises Microsoft Exchange users on Sept. 29, 2022. Even organizations that use Exchange Online may still be affected if they run a hybrid server. Cisco Talos is closely monitoring the recent reports of exploitation attempts against these vulnerabilities and strongly recommends users implement mitigation steps while waiting for securit...
Cisco Talos has released new coverage to detect and prevent the exploitation of two recently disclosed vulnerabilities collectively referred to as "ProxyNotShell," affecting Microsoft Exchange Servers 2013, 2016 and 2019. One of these vulnerabilities could allow an attacker to execute remote code on the targeted server. Limited exploitation of these vulnerabilities in the wild has been reported. CVE-2022-41040 is a Server Side Request Forgery (SSRF) vulnerability, while CVE-2022-41082 enables Remote Code Execution (RCE) when PowerShell is accessible to the attackers. While no fixes or patches are available yet, Microsoft has provided mitigations for on-premises Microsoft Exchange users on Sept. 29, 2022. Even organizations that use Exchange Online may still be affected if they run a hybrid server. Cisco Talos is closely monitoring the recent reports of exploitation attempts against these vulnerabilities and strongly recommends users implement mitigation steps while waiting for securit...
Even organizations that use Exchange Online may still be affected if they run a hybrid server.
Even organizations that use Exchange Online may still be affected if they run a hybrid server.
By Deeba Ahmed The latest attack against Exchange servers utilizes at least two new flaws (CVE-2022-41040, CVE-2022-41082) that have been assigned CVSS scores of 6.3 and 8.8. This is a post from HackRead.com Read the original post: Microsoft Confirms Two 0-Days Being Exploited Against Exchange Servers
By Deeba Ahmed The latest attack against Exchange servers utilizes at least two new flaws (CVE-2022-41040, CVE-2022-41082) that have been assigned CVSS scores of 6.3 and 8.8. This is a post from HackRead.com Read the original post: Microsoft Confirms Two 0-Days Being Exploited Against Exchange Servers
The "ProxyNotShell" security vulnerabilities can be chained for remote code execution and total takeover of corporate email platforms.
The "ProxyNotShell" security vulnerabilities can be chained for remote code execution and total takeover of corporate email platforms.