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: 2026-03-04
Score: 9.3 Critical
EPSS: < 1% Very Low
KEV: No
Impact: Remote Authentication Bypass via Forged JWTs
Action: Immediate Patch
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Github GHSA Github GHSA GHSA-pm7g-w2cf-q238 pac4j-jwt: JwtAuthenticator Authentication Bypass via JWE-Wrapped PlainJWT
History

Tue, 10 Mar 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 10, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L'}

cvssV4_0

{'score': 10, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L'}

cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 9.3, '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'}


Thu, 05 Mar 2026 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 04 Mar 2026 22:30:00 +0000

Type Values Removed Values Added
First Time appeared Pac4j
Pac4j pac4j
CPEs cpe:2.3:a:pac4j:pac4j:*:*:*:*:*:*:*:*
Vendors & Products Pac4j
Pac4j pac4j

Wed, 04 Mar 2026 22:00:00 +0000

Type Values Removed Values Added
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.
Title pac4j-jwt JwtAuthenticator Authentication Bypass
Weaknesses CWE-347
References
Metrics cvssV3_1

{'score': 10, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L'}

cvssV4_0

{'score': 10, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-05-11T23:11:42.643Z

Reserved: 2026-03-03T16:42:01.012Z

Link: CVE-2026-29000

cve-icon Vulnrichment

Updated: 2026-03-05T16:21:48.858Z

cve-icon NVD

Status : Deferred

Published: 2026-03-04T22:16:18.783

Modified: 2026-04-16T16:18:36.200

Link: CVE-2026-29000

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-16T13:15:06Z

Weaknesses