{"cve":"CVE-2023-43645","nvd":{"published":"2023-09-27T15:19:34.330","modified":"2026-06-17T06:26:08.630","status":"Modified","description":"OpenFGA is an authorization/permission engine built for developers and inspired by Google Zanzibar. OpenFGA is vulnerable to a denial of service attack when certain Check calls are executed against authorization models that contain circular relationship definitions. When the call is made, it's possible for the server to exhaust resources and die. Users are advised to upgrade to v1.3.2 and update any offending models. There are no known workarounds for this vulnerability. Note that for models which contained cycles or a relation definition that has the relation itself in its evaluation path, checks and queries that require evaluation will no longer be evaluated on v1.3.2+ and will return errors instead. Users who do not have cyclic models are unaffected.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.9},"cwes":["CWE-835"],"references":["https://github.com/openfga/openfga/commit/725296025fd81227c89525808652c6acd4a605f6","https://github.com/openfga/openfga/security/advisories/GHSA-2hm9-h873-pgqh","https://github.com/openfga/openfga/commit/725296025fd81227c89525808652c6acd4a605f6","https://github.com/openfga/openfga/security/advisories/GHSA-2hm9-h873-pgqh"],"products":["openfga:openfga"],"source":"nvd","synced_at":"2026-10-19T21:39:34.467980132+00:00"},"epss":{"cve":"CVE-2023-43645","score":0.00937,"percentile":0.60854,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-2hm9-h873-pgqh","url":"https://osv.dev/vulnerability/GHSA-2hm9-h873-pgqh","summary":"OpenFGA Vulnerable to DoS from circular relationship definitions","modified":"2026-09-10T03:50:03.105890643Z","packages":[{"ecosystem":"Go","name":"github.com/openfga/openfga","purl":"pkg:golang/github.com/openfga/openfga","ranges":["<1.3.2"],"fixed":["1.3.2"]}]},{"id":"GO-2023-2084","url":"https://osv.dev/vulnerability/GO-2023-2084","summary":"OpenFGA Vulnerable to DoS from circular relationship definitions in github.com/openfga/openfga","modified":"2026-03-03T04:54:14.838160Z","packages":[{"ecosystem":"Go","name":"github.com/openfga/openfga","purl":"pkg:golang/github.com/openfga/openfga","ranges":["<1.3.2"],"fixed":["1.3.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}