{"id":"CVE-2026-35039","summary":"fast-jwt Affected by Cache Confusion via cacheKeyBuilder Collisions Can Return Claims From a Different Token (Identity/Authorization Mixup)","details":"fast-jwt provides fast JSON Web Token (JWT) implementation. From 0.0.1 to before 6.2.0, setting up a custom cacheKeyBuilder method which does not properly create unique keys for different tokens can lead to cache collisions. This could cause tokens to be mis-identified during the verification process leading to valid tokens returning claims from different valid tokens and users being mis-identified as other users based on the wrong token. Version 6.2.0 contains a patch.","aliases":["GHSA-rp9m-7r4c-75qg"],"modified":"2026-07-08T08:12:57.924341800Z","published":"2026-04-06T16:59:43.124Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35039.json","cwe_ids":["CWE-1289","CWE-345","CWE-706"],"cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/35xxx/CVE-2026-35039.json"},{"type":"ADVISORY","url":"https://github.com/nearform/fast-jwt/security/advisories/GHSA-rp9m-7r4c-75qg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-35039"},{"type":"FIX","url":"https://github.com/nearform/fast-jwt/commit/de121056c6415b58770c60640881eaec67ac4ceb"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nearform/fast-jwt","events":[{"introduced":"878469bd124161f35b43b38575f9d8a237c65061"},{"fixed":"986a77a7d59964ad6eebe9de5681d9134cc435b4"},{"fixed":"de121056c6415b58770c60640881eaec67ac4ceb"}],"database_specific":{"cpe":"cpe:2.3:a:nearform:fast-jwt:*:*:*:*:*:node.js:*:*","source":["CPE_RANGE","REFERENCES"],"extracted_events":[{"introduced":"0.1.0"},{"fixed":"6.1.0"}]}}],"versions":["v6.1.0","v2.0.0","v1.7.2","v1.7.1","v1.7.0","v1.6.1","v1.6.0","v1.5.4","v1.5.3","v1.5.2","v1.5.1","v1.5.0","v1.4.1","v1.4.0","v1.3.2","v1.3.0","v1.2.0","v1.1.3","v1.1.2","v1.1.1","v1.1.0","v1.0.0","v0.5.1","v0.5.0","v0.4.2","v0.4.1","v0.4.0","v0.3.1","v0.3.0","v0.2.0","v0.1.1","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-35039.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}