{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/memprocfs/","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/"},{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["credential-access","memory-dump","memprocfs"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eMemProcFS is a memory forensics tool that allows users to mount physical memory as a virtual file system. While legitimate uses exist for forensic analysis, adversaries are abusing it to gain unauthorized access to sensitive information. Observed tactics involve mounting memory dumps of compromised systems and extracting credentials, LSA secrets, SAM data, and cached domain credentials. This activity is particularly concerning as it allows threat actors to bypass traditional security measures and directly access sensitive data within the memory space of targeted processes. Unapproved usage of MemProcFS should be considered suspicious and investigated immediately to prevent credential theft and lateral movement.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eThe attacker gains initial access to a system through unspecified means (e.g., exploiting a vulnerability or using stolen credentials).\u003c/li\u003e\n\u003cli\u003eThe attacker obtains a memory dump of the compromised system, which may contain sensitive information.\u003c/li\u003e\n\u003cli\u003eThe attacker executes \u003ccode\u003eMemProcFS.exe\u003c/code\u003e with the \u003ccode\u003e-device\u003c/code\u003e parameter to mount the memory dump as a virtual file system.\u003c/li\u003e\n\u003cli\u003eMemProcFS creates a virtual file system representation of the memory dump, allowing the attacker to browse the memory space as files and directories.\u003c/li\u003e\n\u003cli\u003eThe attacker accesses the memory of the LSASS process (lsass.exe) through the mounted file system.\u003c/li\u003e\n\u003cli\u003eThe attacker extracts credentials, such as usernames and passwords, from the LSASS process memory.\u003c/li\u003e\n\u003cli\u003eThe attacker may also access registry hives through the mounted file system to obtain LSA secrets, SAM data, and cached domain credentials.\u003c/li\u003e\n\u003cli\u003eThe attacker uses the stolen credentials for lateral movement, privilege escalation, or data exfiltration.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows threat actors to steal sensitive information, including credentials, LSA secrets, SAM data, and cached domain credentials. Compromised credentials can be used for lateral movement within the network, privilege escalation, and further data breaches. The number of potential victims is unknown, but the severity of the impact is high due to the potential for widespread compromise. Sectors at risk include any organization that stores sensitive data on Windows systems.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026ldquo;Detect MemProcFS Execution with Device Parameter\u0026rdquo; to your SIEM to identify suspicious use of MemProcFS based on process creation events.\u003c/li\u003e\n\u003cli\u003eEnable Sysmon process creation logging to provide the necessary data for the Sigma rules above.\u003c/li\u003e\n\u003cli\u003eMonitor for unusual file system access patterns that may indicate a memory dump being mounted as a virtual file system.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-11-02T12:00:00Z","date_published":"2024-11-02T12:00:00Z","id":"/briefs/2024-11-memprocfs-memory-dump/","summary":"Adversaries use MemProcFS, a memory forensics tool, to mount memory dumps as virtual file systems and extract sensitive information like credentials from LSASS or registry hives.","title":"MemProcFS Usage for Memory Dump Mounting and Credential Access","url":"https://feed.craftedsignal.io/briefs/2024-11-memprocfs-memory-dump/"}],"language":"en","title":"CraftedSignal Threat Feed — Memprocfs","version":"https://jsonfeed.org/version/1.1"}