CVE-2026-29000
Authentication Bypass in pac4j-jwt via Encrypted JWT Forgery
Publication date: 2026-03-04
Last updated on: 2026-03-10
Assigner: VulnCheck
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| pac4j | pac4j-jwt | to 4.5.9 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-347 | The product does not verify, or incorrectly verifies, the cryptographic signature for data. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability exists in pac4j-jwt versions prior to 4.5.9, 5.7.9, and 6.3.3 within the JwtAuthenticator component when processing encrypted JWTs.
It allows remote attackers who have access to the server's RSA public key to create a specially crafted JWE-wrapped PlainJWT containing arbitrary subject and role claims.
This crafted token bypasses signature verification, enabling attackers to authenticate as any user, including administrators.
How can this vulnerability impact me? :
This vulnerability can have severe impacts as it allows attackers to bypass authentication controls.
Attackers can impersonate any user, including privileged administrator accounts, potentially gaining unauthorized access to sensitive data and system functions.
Such unauthorized access can lead to data breaches, system compromise, and loss of trust in the affected application.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
I don't know