CVE-2026-29000
CRITICAL EPSS 92.3%
Published Mar 4, 20263mo ago · Modified Jun 17, 20262w ago
9.3 CVSS 4.0
Published Mar 4, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
92.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-347
References 3
- codeant.ai https://www.codeant.ai/security-research/pac4j-jwt-authentication-bypass-public-key
- pac4j.org https://www.pac4j.org/blog/security-advisory-pac4j-jwt-jwtauthenticator.html
- vulncheck.com https://www.vulncheck.com/advisories/pac4j-jwt-jwtauthenticator-authentication-bypass
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.