{"id":"CVE-2026-62847","revision":"b1217760f7ef487289812fcbd06d23b3","records":[{"revision":"b1217760f7ef487289812fcbd06d23b3","observedAt":"2026-10-31T17:07:14.547+00:00","statement":{"source":"nvd","id":"CVE-2026-62847","aliases":[],"title":"Metalama is a Roslyn-based open-source patterns and architecture toolkit for C#. Prior to 2025.1.18, 2026.0.25 and 2026.1.19, Metalama.Framework and Metalama.Tool load and execute compile-time assemblies, auxiliary executable tools and embe…","description":"Metalama is a Roslyn-based open-source patterns and architecture toolkit for C#. Prior to 2025.1.18, 2026.0.25 and 2026.1.19, Metalama.Framework and Metalama.Tool load and execute compile-time assemblies, auxiliary executable tools and embedded helper assemblies from predictable temporary directories. On `Linux` and `macOS`, the default `Path.GetTempPath()` location is world-writable, and existing artifacts are trusted based on sentinel or `.completed` marker files rather than integrity verification. A local unprivileged user on a shared machine or CI/build agent can pre-create the deterministic directory structure and plant a malicious DLL with the matching sentinel. When a higher-privileged developer or build account subsequently builds, Metalama skips regeneration and executes the planted artifact in the compiler, IDE or MSBuild process as the building user. This permits cross-user privilege escalation, reading source and secrets, supply-chain tampering with build output, or disrupting builds. Default Windows per-user temporary directories are protected by ACLs and are not affected. Deployer-selected insecure cache locations are outside the vulnerability's scope. This issue is fixed in versions 2025.1.18, 2026.0.25 and 2026.1.19.","state":0,"publishedAt":"2026-10-30T21:17:13.807+00:00","modifiedAt":"2026-10-30T23:17:12.923+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H","score":8.2,"severity":"HIGH"}],"references":["https://github.com/metalama/Metalama/commit/09911349a916e82194b1cfaa6d0a38acad928fc9","https://github.com/metalama/Metalama/commit/92c4feecfce86d18fcb007ab6d3a1b4383326a2e","https://github.com/metalama/Metalama/pull/1650","https://github.com/metalama/Metalama/releases/tag/release/2025.1.18","https://github.com/metalama/Metalama/releases/tag/release/2026.0.25","https://github.com/metalama/Metalama/releases/tag/release/2026.1.19","https://github.com/metalama/Metalama/security/advisories/GHSA-m6wq-39m7-9xpp"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-62847","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Received","weaknesses":["CWE-377","CWE-427"],"productCriteria":[],"sourceDates":{"published":"2026-10-30T21:17:13.807","lastModified":"2026-10-30T23:17:12.923"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-62847","identifiers":["CVE-2026-62847"]},"retained":false,"historicalAffected":[]}],"coverage":[]}