Security
Headlines
HeadlinesLatestCVEs

Headline

Researchers Develop Exploit Code for Critical Fortinet VPN Bug

Some 340,000 FortiGate SSL VPN appliances remain exposed to the threat more than three weeks after Fortinet released firmware updates to address the issue.

DARKReading
#vulnerability#ios#windows#cisco#rce#buffer_overflow#auth#ssl

Researchers have written exploit code for a critical remote code execution (RCE) vulnerability in Fortinet’s FortiGate SSL VPNs that the vendor disclosed and patched in June 2023.

Bishop Fox’s research team, which developed the exploit, has estimated there are some 340,000 affected FortiGate devices that are currently unpatched against the flaw and remain open to attack. That number is significantly higher than the 250,000 FortiGate devices that several researchers estimated were vulnerable to exploit when Fortinet first disclosed the flaw on June 12.

Code Not Released Publicly — but There’s a GIF

“There are 490,000 affected [FortiGate] SSL VPN interfaces exposed on the internet, and roughly 69% of them are currently unpatched,” Bishop Fox’s director of capability development, Caleb Gross, wrote in a blog post on June 30. “You should patch yours now.”

The heap-based buffer overflow vulnerability, tracked as CVE-2023-27997, affects multiple versions of FortiOS and FortiProxy SSL-VPN software. It gives an unauthenticated, remote attacker a way to execute arbitrary code on an affected device and take complete control of it. Researchers from French cybersecurity firm Lexfo who discovered the flaw assessed it as affecting every single SSL VPN appliance running FortiOS.

Bishop Fox has not released its exploit code publicly. But its blog post has a GIF of it in use. Gross described the exploit that Bishop Fox has developed as giving attackers a way to open an interactive shell they could use to communicate with an affected FortiGate appliance.

“This exploit very closely follows the steps detailed in the original blog post by Lexfo, though we had to take a few extra steps that were not mentioned in that post,” Gross wrote. “The exploit runs in approximately one second, which is significantly faster than the demo video on a 64-bit device shown by Lexfo.”

Fortinet issued firmware updates that addressed the issue on June 12. At the time, the company said the flaw affected organizations in government, manufacturing and other critical infrastructure sectors. Fortinet said it was aware of an attacker exploiting the vulnerability in a limited number of cases.

Fortinet cautioned about the potential for threat actors like those behind the Volt Typhoon cyber-espionage campaign to abuse CVE-2023-27997. Volt Typhoon is a China-based group that is believed to have established persistent access on networks belonging to US telecom companies and other critical infrastructure organizations, for stealing sensitive data and carrying out other malicious actions. The campaign so far has primarily used another, older Fortinet flaw (CVE-2022-40684) for initial access. But organizations should not discount the possibility of Volt Typhoon — and other threat actors — using CVE-2023-27997 either, Fortinet warned.

Why Security Appliances Make Popular Targets

CVE-2023-27997 is one of numerous critical Fortinet vulnerabilities that have been exposed. Like that of almost every other firewall and VPN vendor, Fortinet’s appliances are a popular target for adversaries because of the access they provide to enterprise networks.

The US Cybersecurity and Infrastructure Security Agency (CISA), the National Security Agency (NSA), and others have issued multiple advisories in recent years about the need for organizations to promptly address vulnerabilities in these and other network devices because of the high attacker interest in them.

In June 2022, for instance, CISA warned of China-sponsored threat actors actively targeting unpatched vulnerabilities in network devices from a wide range of vendors. The advisory included a list of the most common of these vulnerabilities. The list included vulnerabilities in products from Fortinet, Cisco, Citrix, Netgear, Pulse, QNAP, and Zyxel.

Systems administrators should patch as quickly as possible, even though patching firmware can be a bit more cumbersome when dealing with appliances that run application gateways, says Timothy Morris, chief security adviser at Tanium. Often, appliances such as those from Fortinet face the perimeter and have very high-availability requirements, meaning they have tight windows for change.

“For most organizations, a certain amount of downtime is probably inevitable,” Morris says. Vulnerabilities such as CVE-2023-27997 require the full firmware image to be reloaded, so there is a certain amount of time and risk involved, he adds. “Configurations have to be backed up and restored to make sure they are working as expected.”

Related news

Chinese Hackers Target Japanese Firms with LODEINFO and NOOPDOOR Malware

Japanese organizations are the target of a Chinese nation-state threat actor that leverages malware families like LODEINFO and NOOPDOOR to harvest sensitive information from compromised hosts while stealthily remaining under the radar in some cases for a time period ranging from two to three years. Israeli cybersecurity company Cybereason is tracking the campaign under the name Cuckoo Spear,

Fortinet FortiOS Out-Of-Bounds Write

Fortinet FortiOS suffers from an out of bounds write vulnerability. Affected includes Fortinet FortiOS versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.6, 7.0.0 through 7.0.13, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, 6.0.0 through 6.0.17, FortiProxy versions 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14, 2.0.0 through 2.0.13, 1.2.0 through 1.2.13, 1.1.0 through 1.1.6, and 1.0.0 through 1.0.7.

Fortinet Warns of Critical FortiOS SSL VPN Vulnerability Under Active Exploitation

Fortinet has disclosed a new critical security flaw in FortiOS SSL VPN that it said is likely being exploited in the wild. The vulnerability, CVE-2024-21762 (CVSS score: 9.6), allows for the execution of arbitrary code and commands. "A out-of-bounds write vulnerability [CWE-787] in FortiOS may allow a remote unauthenticated attacker to execute arbitrary code or command via specially

Critical RCE Vulnerability Puts 330,000 Fortinet Firewalls at Risk

By Deeba Ahmed The vulnerability has a CVSS score of 9.8 out of 10, is a critical security bug that affects Fortinet appliances and has been actively exploited in the wild. This is a post from HackRead.com Read the original post: Critical RCE Vulnerability Puts 330,000 Fortinet Firewalls at Risk

Alert: 330,000 FortiGate Firewalls Still Unpatched to CVE-2023-27997 RCE Flaw

No less than 330000 FortiGate firewalls are still unpatched and vulnerable to CVE-2023-27997, a critical security flaw affecting Fortinet devices that have come under active exploitation in the wild. Cybersecurity firm Bishop Fox, in a report published last week, said that out of nearly 490,000 Fortinet SSL-VPN interfaces exposed on the internet, about 69 percent remain unpatched. CVE-2023-27997

New Fortinet's FortiNAC Vulnerability Exposes Networks to Code Execution Attacks

Fortinet has rolled out updates to address a critical security vulnerability impacting its FortiNAC network access control solution that could lead to the execution of arbitrary code. Tracked as CVE-2023-33299, the flaw is rated 9.6 out of 10 for severity on the CVSS scoring system. It has been described as a case of Java untrusted object deserialization. "A deserialization of untrusted data

CISA Order Highlights Persistent Risk at Network Edge

The U.S. government agency in charge of improving the nation's cybersecurity posture is ordering all federal civilian agencies to take new measures to restrict access to Internet-exposed networking equipment. The directive comes amid a surge in attacks targeting previously unknown vulnerabilities in widely used security and networking appliances.

Fortinet: Patched Critical Flaw May Have Been Exploited

Users urged to apply updates to FortiOS SSL-VPN after attackers may have leveraged a recently discovered vulnerability in attacks against government, manufacturing, and critical infrastructure organizations.

CVE-2023-27997: Fortiguard

A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.

Critical FortiOS and FortiProxy Vulnerability Likely Exploited - Patch Now!

Fortinet on Monday disclosed that a newly patched critical flaw impacting FortiOS and FortiProxy may have been "exploited in a limited number of cases" in attacks targeting government, manufacturing, and critical infrastructure sectors. The vulnerability, tracked as CVE-2023-27997 (CVSS score: 9.2), concerns a heap-based buffer overflow vulnerability in FortiOS and FortiProxy SSL-VPN that could

Critical RCE Flaw Discovered in Fortinet FortiGate Firewalls - Patch Now!

Fortinet has released patches to address a critical security flaw in its FortiGate firewalls that could be abused by a threat actor to achieve remote code execution. The vulnerability, tracked as CVE-2023-27997, is "reachable pre-authentication, on every SSL VPN appliance," Lexfo Security researcher Charles Fol, who discovered and reported the flaw, said in a tweet over the weekend. Details

Fortinet 7.2.1 Authentication Bypass

Fortinet FortiOS, FortiProxy, and FortiSwitchManager version 7.2.1 suffers from a authentication bypass vulnerability.

Fortinet Warns of Active Exploitation of New SSL-VPN Pre-auth RCE Vulnerability

Fortinet on Monday issued emergency patches for a severe security flaw affecting its FortiOS SSL-VPN product that it said is being actively exploited in the wild. Tracked as CVE-2022-42475 (CVSS score: 9.3), the critical bug relates to a heap-based buffer overflow vulnerability that could allow an unauthenticated attacker to execute arbitrary code via specially crafted requests. The company said

Cyberattackers Selling Access to Networks Compromised via Recent Fortinet Flaw

The vulnerability, disclosed In October, gives an unauthenticated attacker a way to take control of an affected product.

Critical Flaw Exploited to Bypass Fortinet Products and Compromise Orgs

By Waqas The flaw is tracked as CVE-2022-40684 in FortiOS, while its exploit is being sold on a popular Russian hacker forum. This is a post from HackRead.com Read the original post: Critical Flaw Exploited to Bypass Fortinet Products and Compromise Orgs

Fortinet FortiOS / FortiProxy / FortiSwitchManager Authentication Bypass

This Metasploit module exploits an authentication bypass vulnerability in the Fortinet FortiOS, FortiProxy, and FortiSwitchManager API to gain access to a chosen account and then adds an SSH key to the authorized_keys file of the chosen account, allowing you to login to the system with the chosen account. Successful exploitation results in remote code execution.

Concerns Over Fortinet Flaw Mount; PoC Released, Exploit Activity Grows

The authentication bypass flaw in FortiOS, FortiProxy and FortiSwitchManager is easy to find and exploit, security experts say.

PoC Exploit Released for Critical Fortinet Auth Bypass Bug Under Active Attacks

A proof-of-concept (PoC) exploit code has been made available for the recently disclosed critical security flaw affecting Fortinet FortiOS, FortiProxy, and FortiSwitchManager, making it imperative that users move quickly to apply the patches. "FortiOS exposes a management web portal that allows a user to configure the system," Horizon3.ai researcher James Horseman said. "Additionally, a user can

Fortinet Warns of Active Exploitation of Newly Discovered Critical Auth Bypass Bug

Fortinet on Monday revealed that the newly patched critical security vulnerability impacting its firewall and proxy products is being actively exploited in the wild. Tracked as CVE-2022-40684 (CVSS score: 9.6), the flaw relates to an authentication bypass in FortiOS, FortiProxy, and FortiSwitchManager that could allow a remote attacker to perform unauthorized operations on the administrative

Patch Now: Fortinet FortiGate & FortiProxy Contain Critical Vuln

The bug is under active exploitation; Fortinet issued a customer advisory urging customers to apply its update immediately.

DARKReading: Latest News

MITRE Launches AI Incident Sharing Initiative