{"id":"CVE-2026-25537","aliases":["GHSA-h395-gr6q-cpjc"],"url":"https://o3.security/vulnerability/CVE-2026-25537","summary":"jsonwebtoken has Type Confusion that leads to potential authorization bypass","details":"jsonwebtoken is a JWT lib in rust. Prior to version 10.3.0, there is a Type Confusion vulnerability in jsonwebtoken, specifically, in its claim validation logic. When a standard claim (such as nbf or exp) is provided with an incorrect JSON type (Like a String instead of a Number), the library’s internal parsing mechanism marks the claim as “FailedToParse”. Crucially, the validation logic treats this “FailedToParse” state identically to “NotPresent”. This means that if a check is enabled (like: validate_nbf = true), but the claim is not explicitly marked as required in required_spec_claims, the library will skip the validation check entirely for the malformed claim, treating it as if it were not there. This allows attackers to bypass critical time-based security restrictions (like “Not Before” checks) and commit potential authentication and authorization bypasses. This issue has been patched in version 10.3.0.","published":"2026-02-04T21:31:53.511Z","modified":"2026-07-15T01:49:20.780702418Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"jsonwebtoken","fixedVersion":"10.3.0"}],"fix":{"url":"https://github.com/Keats/jsonwebtoken/commit/abbc3076742c4161347bc6b8bf4aa5eb86e1dc01","label":"Keats/jsonwebtoken@abbc307"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25537.json"},{"type":"ADVISORY","url":"https://github.com/Keats/jsonwebtoken/security/advisories/GHSA-h395-gr6q-cpjc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-25537"},{"type":"FIX","url":"https://github.com/Keats/jsonwebtoken/commit/abbc3076742c4161347bc6b8bf4aa5eb86e1dc01"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:49:20.780702418Z"}}