{"id":"CVE-2017-12972","url":"https://www.cyber-defence.io/tools/cve/CVE-2017-12972","generatedAt":"2026-10-28T20:06:03.615Z","title":"In Nimbus JOSE+JWT before 4.39, there is no integer-overflow check when converting length values from bytes to bits, which allows attackers to conduct HMAC bypass attacks by shifting Additional Authenticated Data (AAD) and ciphertext so that different…","description":"In Nimbus JOSE+JWT before 4.39, there is no integer-overflow check when converting length values from bytes to bits, which allows attackers to conduct HMAC bypass attacks by shifting Additional Authenticated Data (AAD) and ciphertext so that different plaintext is obtained for the same HMAC.","published":"2017-08-20T16:29:00.000Z","lastModified":"2026-06-17T01:04:14.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":7.5,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"},"cwe":["CWE-345"],"affected":["connect2id/nimbus jose\\+jwt"],"epss":{"score":0.00888,"percentile":0.59136,"date":"2026-10-27","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.89%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/commits/0d2bd649ea386539220d4facfe1f65eb1dadb86c","tags":["Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/issues/224/byte-to-bit-overflow-in-cbc","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/src/master/CHANGELOG.txt","tags":["Release Notes","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://lists.apache.org/thread.html/9317fd092b257a0815434b116a8af8daea6e920b6673f4fd5583d5fe%40%3Ccommits.druid.apache.org%3E","source":"cve@mitre.org"},{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/commits/0d2bd649ea386539220d4facfe1f65eb1dadb86c","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/issues/224/byte-to-bit-overflow-in-cbc","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bitbucket.org/connect2id/nimbus-jose-jwt/src/master/CHANGELOG.txt","tags":["Release Notes","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.apache.org/thread.html/9317fd092b257a0815434b116a8af8daea6e920b6673f4fd5583d5fe%40%3Ccommits.druid.apache.org%3E","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2017-12972","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}