CVE-2026-62847

{"id": "CVE-2026-62847", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-62847", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-10-30T21:21:14.933972Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 8.2, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 6.0, "exploitabilityScore": 1.5}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "metalama", "product": "Metalama", "versions": [{"status": "affected", "version": "< 2025.1.18"}, {"status": "affected", "version": ">= 2025.2.0-preview, <= 2025.2.5-rc"}, {"status": "affected", "version": ">= 2026.0.0-preview, < 2026.0.25"}, {"status": "affected", "version": ">= 2026.1.0-preview, < 2026.1.19"}]}]}], "published": "2026-10-30T21:17:13.807", "references": [{"url": "https://github.com/metalama/Metalama/commit/09911349a916e82194b1cfaa6d0a38acad928fc9", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/commit/92c4feecfce86d18fcb007ab6d3a1b4383326a2e", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/pull/1650", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/releases/tag/release/2025.1.18", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/releases/tag/release/2026.0.25", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/releases/tag/release/2026.1.19", "source": "security-advisories@github.com"}, {"url": "https://github.com/metalama/Metalama/security/advisories/GHSA-m6wq-39m7-9xpp", "source": "security-advisories@github.com"}], "vulnStatus": "Received", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-377"}, {"lang": "en", "value": "CWE-427"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-10-30T23:17:12.923", "sourceIdentifier": "security-advisories@github.com"}