{"id":"CVE-2026-35039","state":"PUBLISHED","title":"fast-jwt Affected by Cache Confusion via cacheKeyBuilder Collisions Can Return Claims From a Different Token (Identity/Authorization Mixup)","description":"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.","publishedAt":"2026-04-06T16:59:43.124Z","updatedAt":"2026-05-13T15:12:43.989Z","severity":{"score":9.1,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["nearform fast-jwt"],"affected":[{"vendor":"nearform","product":"fast-jwt","versions":[{"version":">= 0.0.1, < 6.2.0","status":"affected"}]}],"references":["https://github.com/nearform/fast-jwt/security/advisories/GHSA-rp9m-7r4c-75qg","https://github.com/nearform/fast-jwt/commit/de121056c6415b58770c60640881eaec67ac4ceb"],"weaknesses":["CWE-345","CWE-706","CWE-1289"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/35xxx/CVE-2026-35039.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-35039","state":"PUBLISHED","datePublished":"2026-04-06T16:59:43.124Z","dateUpdated":"2026-05-13T15:12:43.989Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-03-31T21:06:06.428Z"},"containers":{"cna":{"title":"fast-jwt Affected by Cache Confusion via cacheKeyBuilder Collisions Can Return Claims From a Different Token (Identity/Authorization Mixup)","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"nearform","product":"fast-jwt","versions":[{"version":">= 0.0.1, < 6.2.0","status":"affected"}]}],"references":[{"url":"https://github.com/nearform/fast-jwt/security/advisories/GHSA-rp9m-7r4c-75qg","name":"https://github.com/nearform/fast-jwt/security/advisories/GHSA-rp9m-7r4c-75qg","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/nearform/fast-jwt/commit/de121056c6415b58770c60640881eaec67ac4ceb","name":"https://github.com/nearform/fast-jwt/commit/de121056c6415b58770c60640881eaec67ac4ceb","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":9.1,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-345","lang":"en","description":"CWE-345: Insufficient Verification of Data Authenticity","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-706","lang":"en","description":"CWE-706: Use of Incorrectly-Resolved Name or Reference","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1289","lang":"en","description":"CWE-1289: Improper Validation of Unsafe Equivalence in Input","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-04-08T11:54:39.776Z"},"source":{"advisory":"GHSA-rp9m-7r4c-75qg","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-07T14:25:32.378641Z","id":"CVE-2026-35039","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-13T15:12:43.989Z"}}]}}}