{"id":"CVE-2026-66065","aliases":["GHSA-jv2h-4p9v-wf5w"],"url":"https://o3.security/vulnerability/CVE-2026-66065","summary":"Ouroboros: Untrusted project .env can still reach RCE via omitted execution-routing keys (Incomplete fix of CVE-2026-47211)","details":"Ouroboros is a local-first runtime for AI coding agents that records their actions and applies user-defined policies to constrain behavior. Versions prior to 0.42.1 have an incomplete denylist. Several execution-routing keys of the same RCE class were omitted, so a malicious cloned repo can still reach arbitrary command execution by shipping a .env (auto-loaded at import, with no review step). The CVE-2026-47211 fix added _UNTRUSTED_ENV_DENYLIST to stop an untrusted project-directory .env from redirecting execution, but it did not account for all keys. The backend config-home and MCP/plugin roots bypass the approval gate by pointing the nested agent, MCP servers, and plugin roster at attacker config. Other variables re-enable blocked local transports, replace sub-agent prompts, switch backends, and lower tool approval classes, further weakening the approval gate. This issue has been fixed in version 0.42.1.","published":"2026-08-03T20:20:27.599Z","modified":"2026-08-12T03:51:28.743890415Z","cvss":null,"epss":{"score":0.00297,"percentile":0.2199,"asOf":"2026-09-07"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"PyPI","name":"ouroboros-ai","fixedVersion":"0.42.1"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/Q00/ouroboros/releases/tag/v0.42.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66065.json"},{"type":"ADVISORY","url":"https://github.com/Q00/ouroboros/security/advisories/GHSA-jv2h-4p9v-wf5w"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66065"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:28.743890415Z"}}