{"id":"CVE-2026-55689","aliases":["GHSA-hcxc-wf8j-23hv","GO-2026-5423"],"url":"https://o3.security/vulnerability/CVE-2026-55689","summary":"OpenFGA: OIDC audience validation skipped when --authn-oidc-audience is unset","details":"## Description\n\nOpenFGA's OIDC authenticator skipped JWT audience (`aud`) validation when no audience was configured.\nIn deployments where one identity provider issues tokens for multiple services,\na token minted for an unrelated service could authenticate to OpenFGA.\n\n## Preconditions\n\nThis applies if the following preconditions are met:\n\n1. You run OpenFGA with `authn.method` set to `oidc`.\n2. You configured `authn.oidc.issuer` but did **not** set\n   `authn.oidc.audience` (`--authn-oidc-audience` / `OPENFGA_AUTHN_OIDC_AUDIENCE`).\n\n## Fix\n\nUpgrade to OpenFGA 1.18.0 or greater. OpenFGA now refuses to start in `oidc`\nmode unless both `authn.oidc.issuer` and `authn.oidc.audience` are set, and the\n`aud` claim is always validated.\n\n## Acknowledgements\n\nOpenFGA would like to thank https://github.com/0xVijay for the report.","published":"2026-07-09T21:06:22.543Z","modified":"2026-08-12T03:51:21.029896946Z","cvss":{"score":6.8,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N"},"epss":{"score":0.00407,"percentile":0.34249,"asOf":"2026-09-12"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/openfga/openfga","fixedVersion":"1.18.0"}],"fix":{"url":"https://github.com/openfga/openfga/commit/44596773b2e62738720ef215bf7fa04352954271","label":"openfga/openfga@4459677"},"references":[{"type":"WEB","url":"https://github.com/openfga/helm-charts/releases/tag/openfga-0.3.9"},{"type":"WEB","url":"https://github.com/openfga/openfga/releases/tag/v1.18.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55689.json"},{"type":"ADVISORY","url":"https://github.com/openfga/openfga/security/advisories/GHSA-hcxc-wf8j-23hv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55689"},{"type":"FIX","url":"https://github.com/openfga/openfga/commit/44596773b2e62738720ef215bf7fa04352954271"},{"type":"PACKAGE","url":"https://github.com/openfga/helm-ch"},{"type":"PACKAGE","url":"https://github.com/openfga/openfga"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:21.029896946Z"}}