{"id":"CVE-2017-18239","url":"https://www.cyber-defence.io/tools/cve/CVE-2017-18239","generatedAt":"2026-10-28T19:47:34.054Z","title":"A time-sensitive equality check on the JWT signature in the JsonWebToken.validate method in main/scala/authentikat/jwt/JsonWebToken.scala in authentikat-jwt (aka com.jason-goodwin/authentikat-jwt) version 0.4.5 and earlier allows the supplier of a JWT…","description":"A time-sensitive equality check on the JWT signature in the JsonWebToken.validate method in main/scala/authentikat/jwt/JsonWebToken.scala in authentikat-jwt (aka com.jason-goodwin/authentikat-jwt) version 0.4.5 and earlier allows the supplier of a JWT token to guess bit after bit of the signature by repeating validation requests.","published":"2018-03-18T03:29:00.000Z","lastModified":"2026-06-17T01:12:28.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"3.0","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":[],"affected":["authentikat-jwt project/authentikat-jwt"],"epss":{"score":0.01963,"percentile":0.80231,"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 (1.96%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://github.com/jasongoodwin/authentikat-jwt/commit/2d2fa0d40ac8f2f7aa7e9b070fa1a25eee082cb0","tags":["Patch","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/jasongoodwin/authentikat-jwt/issues/12","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/jasongoodwin/authentikat-jwt/pull/36","tags":["Issue Tracking","Third Party Advisory"],"source":"cve@mitre.org"},{"url":"https://github.com/jasongoodwin/authentikat-jwt/commit/2d2fa0d40ac8f2f7aa7e9b070fa1a25eee082cb0","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/jasongoodwin/authentikat-jwt/issues/12","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://github.com/jasongoodwin/authentikat-jwt/pull/36","tags":["Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2017-18239","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."}