{"id":"CVE-2026-29000","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-29000","generatedAt":"2026-10-28T04:36:47.442Z","title":"pac4j-jwt versions prior to 4.5.9, 5.7.9, and 6.3.3 contain an authentication bypass vulnerability in JwtAuthenticator when processing encrypted JWTs that allows remote attackers to forge authentication tokens.","description":"pac4j-jwt versions prior to 4.5.9, 5.7.9, and 6.3.3 contain an authentication bypass vulnerability in JwtAuthenticator when processing encrypted JWTs that allows remote attackers to forge authentication tokens. Attackers who possess the server's RSA public key can create a JWE-wrapped PlainJWT with arbitrary subject and role claims, bypassing signature verification to authenticate as any user including administrators.","published":"2026-03-04T22:16:19.000Z","lastModified":"2026-10-08T16:17:13.000Z","status":"Deferred","sourceIdentifier":"disclosure@vulncheck.com","cvss":{"version":"4.0","score":9.3,"severity":"CRITICAL","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-347"],"affected":[],"epss":{"score":0.06088,"percentile":0.93377,"date":"2026-10-27","history":[{"date":"2026-09-24","score":0.00483,"percentile":0.3898},{"date":"2026-10-25","score":0.06088,"percentile":0.93364}]},"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 (6.09%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-10-25T00:00:00.000Z","detail":{"to":0.06088,"from":0.00513,"percentile":0.93364},"summary":"EPSS moved from 0.5% to 6.1% probability of exploitation in the next thirty days."}],"references":[{"url":"https://www.codeant.ai/security-research/pac4j-jwt-authentication-bypass-public-key","source":"disclosure@vulncheck.com"},{"url":"https://www.pac4j.org/blog/security-advisory-pac4j-jwt-jwtauthenticator.html","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/pac4j-jwt-jwtauthenticator-authentication-bypass","source":"disclosure@vulncheck.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-29000","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."}