{"id":"CVE-2026-35041","summary":"ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification","details":"fast-jwt provides fast JSON Web Token (JWT) implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the supplied RegExp, a crafted JWT can trigger catastrophic backtracking in the JavaScript regex engine, resulting in significant CPU consumption during verification. This vulnerability is fixed in 6.2.1.","aliases":["GHSA-cjw9-ghj4-fwxf"],"modified":"2026-07-08T08:09:28.006981201Z","published":"2026-04-09T14:55:22.807Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-1333"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35041.json"},"references":[{"type":"WEB","url":"https://github.com/nearform/fast-jwt/releases/tag/v6.2.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35041.json"},{"type":"ADVISORY","url":"https://github.com/nearform/fast-jwt/security/advisories/GHSA-cjw9-ghj4-fwxf"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-35041"},{"type":"FIX","url":"https://github.com/nearform/fast-jwt/commit/b0be0ca161593836a153d5180ca5358ad9b5de94"},{"type":"FIX","url":"https://github.com/nearform/fast-jwt/pull/595"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nearform/fast-jwt","events":[{"introduced":"72f91b547f5dca90715a70ff3cbaa042e40d8803"},{"fixed":"6b13fe96614a38613d453f46ba0631c4cd09dcd8"},{"fixed":"b0be0ca161593836a153d5180ca5358ad9b5de94"}],"database_specific":{"source":["CPE_RANGE","REFERENCES"],"extracted_events":[{"introduced":"5.0.0"},{"fixed":"6.2.1"}],"cpe":"cpe:2.3:a:nearform:fast-jwt:*:*:*:*:*:node.js:*:*"}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-35041.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H"}]}