The CVE-2024-21412<\/a> flaw in the Microsoft Defender SmartScreen has been exploited to deliver information stealers such as ACR Stealer,\u00a0Lumma, and\u00a0Meduza.<\/h2>\n\n\n\n
Fortinet FortiGuard Labs researchers observed a malware campaign exploiting the vulnerability CVE-2024-21412<\/a>\u00a0(CVSS score: 8.1) to spread information stealer, such as ACR Stealer,\u00a0Lumma<\/a>, and\u00a0Meduza.
The CVE-2024-21412<\/a>\u00a0is an Internet Shortcut Files Security Feature Bypass Vulnerability.
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- Peter Girnus (gothburz) of Trend Micro\u2019s Zero Day Initiative<\/a>\u00a0with\u00a0Trend Micro<\/a><\/li>\n\n\n\n
- dwbzn<\/a>\u00a0with\u00a0Aura Information Security<\/a>
- Dima Lenz and Vlad Stolyarov of Google\u2019s Threat Analysis Group
Microsoft addressed the flaw with the release of Patch Tuesday Security updates for February 2024<\/a>. Fortinet reported that the stealer campaign targeted Spain, Thailand, and the U.S. with booby-trapped files.
“FortiGuard Labs has observed a stealer campaign spreading multiple files that exploit CVE-2024-21412 to download malicious executable files. Initially, attackers lure victims into clicking a crafted link to a URL file designed to download an LNK file. The LNK file then downloads an executable file containing an HTA script. Once executed, the script decodes and decrypts PowerShell code to retrieve the final URLs, decoy PDF files, and a malicious shell code injector. These files aim to inject the final stealer into legitimate processes, initiating malicious activities and sending the stolen data back to a C2 server.” reads the report<\/strong><\/a> published by Fortinet. “The threat actors have designed different injectors to evade detection and use various PDF files to target specific regions, including North America, Spain, and Thailand.”<\/em>
![\"CVE-2024-21412](\"https:\/\/i0.wp.com\/securityaffairs.com\/wp-content\/uploads\/2024\/07\/image-28.png?resize=865%2C407&ssl=1\")
<\/a><\/figure>\n\n\n\nDuring the investigation, the researchers detected multiple LNK files that were used to download similar executables containing an embedded HTA script. The HTA script executed additional malicious code and downloads two files, a decoy PDF designed to divert the victim’s attention and an execution file that injects shell code for the subsequent stages of the attack.
The researchers identified two types of injectors. The first variant downloads a shell code from an image file hosted on Imghippo, which has low detection rates on VirusTotal. The shell code is extracted from the image pixels using the Windows API “GdipBitmapGetPixel” and then executed. This code retrieves necessary APIs, creates a folder, and drops files in the “%TEMP%” directory, including a HijackLoader<\/a>, indicated by specific byte patterns in the data.<\/p>\n\n\n\n
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Pierluigi Paganini<\/strong><\/a><\/p>\n\n\n\n
(<\/strong>SecurityAffairs<\/strong><\/a>\u00a0\u2013<\/strong>\u00a0hacking, CVE-2024-21412)<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"
![\"CVE-2024-21412](\"https:\/\/i0.wp.com\/securityaffairs.com\/wp-content\/uploads\/2024\/07\/image-28.png?ssl=1\")
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