CVE-2026-67546

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{}

{"affected": [{"affectedData": [{"product": "heym", "vendor": "heymrun", "versions": [{"status": "affected", "version": "< 0.0.75"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Heym builds and runs agentic systems and business-process automations on self-hosted infrastructure. Prior to version 0.0.75, the same POST /api/mcp/fetch-tools endpoint (any authenticated user, lowest role) also accepts the stdio transport, which spawns the attacker-supplied command with attacker-supplied args and an environment merged over os.environ. The process executes on the shared backend host before MCP protocol validation fails \u2014 so side effects fire regardless of whether the command speaks MCP. This is a distinct weakness class and exploit primitive from the SSRF (Advisory 2) on the same endpoint, and needs a different fix (role gating / opt-in trust boundary rather than egress controls). This issue has been patched in version 0.0.75."}], "id": "CVE-2026-67546", "lastModified": "2026-11-12T18:17:52.973", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 5.9, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-67546", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-11-12T16:31:22.524253Z", "version": "2.0.3"}}]}, "published": "2026-11-11T22:17:29.533", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/heymrun/heym/commit/22b8ee60eb92128cf4ff04a9b6c0e1b62bf25a01"}, {"source": "security-advisories@github.com", "url": "https://github.com/heymrun/heym/commit/6c6213f88dfa8b2a70d23a9a271171241e910904"}, {"source": "security-advisories@github.com", "url": "https://github.com/heymrun/heym/releases/tag/v0.0.75"}, {"source": "security-advisories@github.com", "url": "https://github.com/heymrun/heym/security/advisories/GHSA-378x-q589-34mv"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-94"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,0.0.75)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "heym", "source": "cna", "vendor": "heymrun"}, "product": "heym", "vendor": "heymrun"}], "created": "2026-11-12T21:15:09.127402+00:00", "updated": "2026-11-13T07:30:12.029757+00:00", "vendors": ["heymrun", "heymrun$PRODUCT$heym"]}