{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-40031/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":7.8,"id":"CVE-2026-40031"}],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["dll-hijacking","library-hijacking","code-execution","memprocfs","cve-2026-40031"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eMemProcFS before version 5.17 is vulnerable to DLL and shared library hijacking due to unsafe library loading practices. Specifically, the application uses bare-name \u003ccode\u003eLoadLibraryU\u003c/code\u003e and \u003ccode\u003edlopen\u003c/code\u003e calls without proper path qualification for \u003ccode\u003evmmpyc\u003c/code\u003e, \u003ccode\u003elibMSCompression\u003c/code\u003e, and plugin DLLs. This vulnerability, identified as CVE-2026-40031, exists across six attack surfaces. The vulnerability was reported by VulnCheck. Exploitation can occur on both Windows and Linux systems where MemProcFS is installed.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker identifies a vulnerable MemProcFS installation (version \u0026lt; 5.17).\u003c/li\u003e\n\u003cli\u003eAttacker determines the libraries MemProcFS attempts to load without a fully qualified path, such as \u003ccode\u003evmmpyc\u003c/code\u003e, \u003ccode\u003elibMSCompression\u003c/code\u003e, or plugin DLLs.\u003c/li\u003e\n\u003cli\u003eAttacker crafts a malicious DLL or shared library with the same name as one of the targeted libraries (e.g., \u003ccode\u003evmmpyc.dll\u003c/code\u003e on Windows or \u003ccode\u003elibvmmpyc.so\u003c/code\u003e on Linux).\u003c/li\u003e\n\u003cli\u003eAttacker places the malicious library in the same working directory as MemProcFS or manipulates the \u003ccode\u003eLD_LIBRARY_PATH\u003c/code\u003e environment variable (on Linux) to point to a directory containing the malicious library.\u003c/li\u003e\n\u003cli\u003eThe user executes MemProcFS.\u003c/li\u003e\n\u003cli\u003eMemProcFS attempts to load the legitimate library using \u003ccode\u003eLoadLibraryU\u003c/code\u003e or \u003ccode\u003edlopen\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eDue to the presence of the malicious library in the working directory or the manipulated \u003ccode\u003eLD_LIBRARY_PATH\u003c/code\u003e, the malicious library is loaded instead of the intended legitimate library.\u003c/li\u003e\n\u003cli\u003eThe malicious library executes arbitrary code within the context of the MemProcFS process, granting the attacker control over the system.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-40031 allows an attacker to achieve arbitrary code execution. While the exact number of victims is unknown, any system running a vulnerable version of MemProcFS is at risk. Given the nature of MemProcFS, successful exploitation could lead to sensitive data exposure or complete system compromise.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade MemProcFS to version 5.17 or later to address the vulnerability (References: \u003ca href=\"https://github.com/ufrisk/MemProcFS/releases/tag/v5.17\"\u003ehttps://github.com/ufrisk/MemProcFS/releases/tag/v5.17\u003c/a\u003e).\u003c/li\u003e\n\u003cli\u003eMonitor process creations for MemProcFS loading unexpected DLLs or shared libraries from non-standard paths using the provided Sigma rules.\u003c/li\u003e\n\u003cli\u003eImplement file integrity monitoring for MemProcFS installation directories to detect the presence of newly created DLLs or shared libraries with suspicious names.\u003c/li\u003e\n\u003cli\u003eEducate users about the risks of running applications from untrusted sources and the importance of verifying the integrity of software before execution.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-08T22:16:23Z","date_published":"2026-04-08T22:16:23Z","id":"/briefs/2026-04-memprocfs-dll-hijacking/","summary":"MemProcFS before 5.17 is susceptible to DLL and shared-library hijacking due to unsafe library-loading patterns, allowing attackers to achieve arbitrary code execution by placing malicious libraries or manipulating the library search path.","title":"MemProcFS DLL and Shared Library Hijacking Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-04-memprocfs-dll-hijacking/"}],"language":"en","title":"CraftedSignal Threat Feed — Cve-2026-40031","version":"https://jsonfeed.org/version/1.1"}