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CVE-2026-40458 Detail

Description

PAC4J is vulnerable to Cross-Site Request Forgery (CSRF). A malicious attacker can craft a specially designed website which, when visited by a user, will automatically submit a forged cross-site request with a token whose hash collides with the victim's legitimate CSRF token. Importantly, the attacker does not need to know the victim’s CSRF token or its hash prior to the attack. Collisions in the deterministic String.hashCode() function can be computed directly, reducing the effective token's security space to 32 bits. This bypasses CSRF protection, allowing profile updates, password changes, account linking, and any other state-changing operations to be performed without the victim's consent. This issue was fixed in PAC4J versions 5.7.10 and 6.4.1


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  CERT.PL
CVSS-B 7.0 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://cert.pl/en/posts/2026/04/CVE-2026-40458/ CERT.PL
https://www.pac4j.org/blog/security-advisory-pac4j-core-and-ldap.html CERT.PL

Weakness Enumeration

CWE-ID CWE Name Source
CWE-352 Cross-Site Request Forgery (CSRF) CERT.PL  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-40458
NVD Published Date:
04/17/2026
NVD Last Modified:
04/17/2026
Source:
CERT.PL