{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/ocaml/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":7.3,"id":"CVE-2026-41082"}],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["path-traversal","package-manager","ocaml"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eOCaml opam, a package manager for OCaml, is susceptible to a path traversal vulnerability (CVE-2026-41082) in versions prior to 2.5.1. The vulnerability stems from insufficient validation of filepaths specified within the \u0026ldquo;.install\u0026rdquo; files used to define package installation procedures. Specifically, the \u0026ldquo;.install\u0026rdquo; field, which dictates the destination of installed files, permits the inclusion of \u0026ldquo;../\u0026rdquo; sequences. This oversight can be exploited by malicious package maintainers or compromised repositories to overwrite files outside the intended installation directory. This allows attackers to manipulate critical system files, potentially escalating privileges and compromising the entire system. The impact is significant for developers and systems relying on opam for package management, as it introduces a risk of arbitrary file modification and subsequent system compromise.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker crafts a malicious OCaml package containing a specially crafted \u0026ldquo;.install\u0026rdquo; file.\u003c/li\u003e\n\u003cli\u003eThe malicious \u0026ldquo;.install\u0026rdquo; file contains a destination filepath that utilizes \u0026ldquo;../\u0026rdquo; sequences to traverse to parent directories.\u003c/li\u003e\n\u003cli\u003eA user unknowingly installs the malicious package using \u003ccode\u003eopam install \u0026lt;package\u0026gt;\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eOpam parses the \u0026ldquo;.install\u0026rdquo; file and executes the file installation instructions.\u003c/li\u003e\n\u003cli\u003eDue to the path traversal vulnerability, opam writes files to unintended locations outside of the intended package directory.\u003c/li\u003e\n\u003cli\u003eThe attacker overwrites critical system files, such as configuration files or binaries.\u003c/li\u003e\n\u003cli\u003eThe system is compromised as a result of the overwritten files, potentially leading to privilege escalation or arbitrary code execution.\u003c/li\u003e\n\u003cli\u003eThe attacker gains control of the system.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability can lead to arbitrary file overwrite, potentially resulting in privilege escalation, code execution, and complete system compromise. While the specific number of affected systems is unknown, any system utilizing OCaml opam versions before 2.5.1 is potentially vulnerable. This includes development environments, build servers, and production systems relying on OCaml packages installed through opam. A successful attack could lead to data loss, system instability, or unauthorized access to sensitive information.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade OCaml opam to version 2.5.1 or later to remediate CVE-2026-41082 (see references).\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Opam Path Traversal in Install Files\u003c/code\u003e to detect attempts to exploit this vulnerability by monitoring for suspicious file paths during opam package installation.\u003c/li\u003e\n\u003cli\u003eImplement strict controls over the packages and repositories used by opam to prevent the installation of malicious or compromised packages.\u003c/li\u003e\n\u003cli\u003eRegularly audit the \u0026ldquo;.install\u0026rdquo; files of installed packages for suspicious path traversal sequences.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-17T12:00:00Z","date_published":"2026-04-17T12:00:00Z","id":"/briefs/2026-04-opam-path-traversal/","summary":"OCaml opam before 2.5.1 is vulnerable to path traversal via a crafted .install file, potentially allowing attackers to overwrite arbitrary files.","title":"OCaml opam Path Traversal Vulnerability (CVE-2026-41082)","url":"https://feed.craftedsignal.io/briefs/2026-04-opam-path-traversal/"}],"language":"en","title":"CraftedSignal Threat Feed — Ocaml","version":"https://jsonfeed.org/version/1.1"}