Void Banshee APT Exploits Microsoft MHTML Flaw to Spread Atlantida Stealer
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2021-40444 | Remote Code Execution via MSHTML Rendering Engine in Microsoft Windows/Office (CVE-2021-40444) CVE-2021-40444 is a remote code execution vulnerability in the Microsoft MSHTML browser rendering engine, which Microsoft Office documents can load on Windows systems. It is triggered when a user is convinced to open a specially crafted Office document containing a malicious ActiveX control hosted by the MSHTML engine (tracked as a path-traversal-class issue, CWE-22). A successful attacker gains the ability to run arbitrary code in the context of the logged-on user, with greater impact when that user has administrative rights. Any Windows system that can open Office documents is exposed, spanning Windows 7, 8.1, RT 8.1, Windows 10 (1507 through 21H1) and Windows Server 2004/2008. Exploitation is confirmed in the wild: Microsoft observed targeted attacks at disclosure, the flaw is in CISA's KEV with known ransomware use, and Microsoft released security updates on September 14, 2021. Do: Apply Microsoft's security updates released September 14, 2021 for your Windows version immediately; this is a CISA KEV item with known ransomware use, so patching is treated as mandatory. As interim protection, keep Microsoft Defender Antivirus/Defender for Endpoint signatures current (enterprise detection build 1.349.22.0 or newer, with alerts appearing as 'Suspicious Cpl File Execution') and avoid opening untrusted Office documents, since exploitation requires user interaction with a crafted file. | 8.8 | 97% | KEV ransomware PoC ×2 |
| masshundreds of millions of Windows PCs and servers (nearly all Windows desktop/laptop installs on affected versions at disclosure) | |
| CVE-2024-27198 | Authentication Bypass in JetBrains TeamCity CI/CD Server CVE-2024-27198 is an authentication bypass (CWE-288) in JetBrains TeamCity, JetBrains' self-hosted on-premises continuous integration/continuous delivery (CI/CD) server, that allows an unauthenticated attacker to circumvent login and perform administrative actions. It is triggered by sending specially crafted requests to the TeamCity web interface that dodge the authentication check, after which the attacker gains full administrator access. With admin access, an attacker can create administrative accounts, alter build configurations, plant code that runs on the server and its build agents, and reach source code, credentials, and secrets stored in the CI/CD environment, which ransomware operators have already used as an entry point. Any TeamCity deployment an attacker can reach over the network is affected, with internet-facing instances at the highest risk. Exploitation is confirmed in the wild: CISA added the flaw to the KEV catalog on 2024-03-07 with known ransomware use, and EPSS estimates a 99.9% probability of exploitation within 30 days. Do: Upgrade immediately to the patched TeamCity release per JetBrains' advisory (2023.11.4 or later fixes this vulnerability), or apply vendor mitigations or discontinue use per CISA guidance if patching is not possible. Audit instances for unexpected administrator accounts, modified build configurations, and other signs of compromise, since ransomware operators are known to be actively exploiting this bug. Restrict TeamCity's network exposure to trusted users and networks until the update is applied. | 9.8 | 100% | KEV ransomware |
| largetens of thousands of internet-exposed TeamCity servers (roughly 20,000–30,000 per public scans at disclosure) | |
| CVE-2024-38112 | Windows MSHTML Platform Spoofing Vulnerability Exploited in the Wild (CVE-2024-38112) CVE-2024-38112 is a spoofing flaw (CWE-451) in the Microsoft Windows MSHTML platform, the Windows component used to render web content, including by applications that embed the legacy Internet Explorer engine. It is triggered when a user interacts with attacker-controlled content rendered through MSHTML: the attack requires no privileges, travels over the network, and needs user interaction (UI:R per its CVSS vector), letting an attacker misrepresent critical UI information to the victim. Despite being classified as spoofing, the CVSS impact scores are high across confidentiality, integrity, and availability, and the CVSS base score is 7.5 (High). Any system running the affected Windows 10 (1507, 1607, 1809, 21H2, 22H2), Windows 11 (21H2, 22H2, 23H2), or Windows Server (2008, 2012, 2016, 2019) releases is affected. Exploitation is confirmed in the wild: Microsoft patched it as an actively exploited zero-day in July 2024, CISA added it to the Known Exploited Vulnerabilities catalog on 2024-07-09, and reporting indicates it had been exploited for over a year before the fix. Do: Apply Microsoft's July 2024 security updates (Patch Tuesday) across all affected Windows 10, Windows 11, and Windows Server versions, prioritizing internet-facing and user workstations given confirmed in-the-wild exploitation and the 84.2% EPSS score. Until patched, remind users to avoid interacting with untrusted web or document content, since exploitation requires user interaction. Track the fix against CISA's KEV catalog deadlines and verify patch status on all endpoints. | 7.5 | 84% | KEV |
| masshundreds of millions of Windows devices (essentially all desktops and servers on the listed Windows 10/11 and Windows Server releases) |
Full article644 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananJul 16, 2024Data Security / Vulnerability
An advanced persistent threat (APT) group called Void Banshee has been observed exploiting a recently disclosed security flaw in the Microsoft MHTML browser engine as a zero-day to deliver an information stealer called Atlantida.
Cybersecurity firm Trend Micro, which observed the activity in mid-May 2024, said the vulnerability – tracked as CVE-2024-38112 – was used as part of a multi-stage attack chain using specially crafted internet shortcut (URL) files.
"Variations of the Atlantida campaign have been highly active throughout 2024 and have evolved to use CVE-2024-38112 as part of Void Banshee infection chains," security researchers Peter Girnus and Aliakbar Zahravi said. "The ability of APT groups like Void Banshee to exploit disabled services such as [Internet Explorer] poses a significant threat to organizations worldwide."
The findings dovetail with prior disclosures from Check Point, which told The Hacker News of a campaign leveraging the same shortcoming to distribute the stealer. It's worth noting that CVE-2024-38112 was addressed by Microsoft as part of Patch Tuesday updates last week.
CVE-2024-38112 has been described by the Windows maker as a spoofing vulnerability in the MSHTML (aka Trident) browser engine used in the now-discontinued Internet Explorer browser. However, the Zero Day Initiative (ZDI) has asserted that it's a remote code execution flaw.
"What happens when the vendor states the fix should be a defense-in-depth update rather than a full CVE?," ZDI's Dustin Childs pointed out. "What happens when the vendor states the impact is spoofing but the bug results in remote code execution?"
Attack chains involve the use of spear-phishing emails embedding links to ZIP archive files hosted on file-sharing sites, which contain URL files that exploit CVE-2024-38112 to redirect the victim to a compromised site hosting a malicious HTML Application (HTA).
Opening the HTA file results in the execution of a Visual Basic Script (VBS) that, in turn, downloads and runs a PowerShell script responsible for retrieving a .NET trojan loader, which ultimately uses the Donut shellcode project to decrypt and execute the Atlantida stealer inside RegAsm.exe process memory.
Atlantida, modeled on open-source stealers like NecroStealer and PredatorTheStealer, is designed to extract files, screenshots, geolocation, and sensitive data from web browsers and other applications, including Telegram, Steam, FileZilla, and various cryptocurrency wallets.
"By using specially crafted URL files that contained the MHTML protocol handler and the x-usc! directive, Void Banshee was able to access and run HTML Application (HTA) files directly through the disabled IE process," the researchers said.
"This method of exploitation is similar to CVE-2021-40444, another MSHTML vulnerability that was used in zero-day attacks."
Not much is known about Void Banshee other than the fact that it has a history of targeting North American, European, and Southeast Asian regions for information theft and financial gain.
The development comes as Cloudflare revealed that threat actors are swiftly incorporating proof-of-concept (PoC) exploits into their arsenal, sometimes as quickly as 22 minutes after their public release, as observed in the case of CVE-2024-27198.
"The speed of exploitation of disclosed CVEs is often quicker than the speed at which humans can create WAF rules or create and deploy patches to mitigate attacks," the web infrastructure company said.
It also follows the discovery of a new campaign that leverages Facebook ads promoting fake Windows themes to distribute another stealer known as SYS01stealer that aims to hijack Facebook business accounts and further propagate the malware.
"Being an info-stealer, SYS01 focuses on exfiltrating browser data such as credentials, history, and cookies," Trustwave said. "A big chunk of its payload is focused on obtaining access tokens for Facebook accounts, specifically those with Facebook business accounts, which can aid the threat actors in spreading the malware."
Found this article interesting? Follow us on Google News, Twitter and LinkedIn to read more exclusive content we post.
Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2024/07/void-banshee-apt-exploits-microsoft.html