{"cve":"CVE-2026-35041","nvd":{"published":"2026-04-09T16:16:27.383","modified":"2026-10-26T22:10:00.163","status":"Analyzed","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-1333"],"references":["https://github.com/nearform/fast-jwt/commit/b0be0ca161593836a153d5180ca5358ad9b5de94","https://github.com/nearform/fast-jwt/pull/595","https://github.com/nearform/fast-jwt/releases/tag/v6.2.1","https://github.com/nearform/fast-jwt/security/advisories/GHSA-cjw9-ghj4-fwxf","https://github.com/nearform/fast-jwt/security/advisories/GHSA-cjw9-ghj4-fwxf"],"products":["nearform:fast-jwt"],"source":"nvd","synced_at":"2026-10-26T22:26:44.656832877+00:00"},"epss":{"cve":"CVE-2026-35041","score":0.00262,"percentile":0.17846,"date":"2026-10-26"},"kev":null,"osv":[{"id":"GHSA-cjw9-ghj4-fwxf","url":"https://osv.dev/vulnerability/GHSA-cjw9-ghj4-fwxf","summary":"fast-jwt has a ReDoS when using RegExp in allowed* leading to CPU exhaustion during token verification","modified":"2026-04-09T19:19:01.951859Z","packages":[{"ecosystem":"npm","name":"fast-jwt","purl":"pkg:npm/fast-jwt","ranges":[">=5.0.0 <6.2.1"],"fixed":["6.2.1"]}]}],"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."]}