CVE-2026-40459
CVE-2026-40459 is a high-severity vulnerability in Pac4j with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-90.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v4: 8.7
- EPSS exploit prediction: 1% (45th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-23423
- Weakness: CWE-90
- Affected product: Pac4j
- Published:
- Last modified:
Description
PAC4J is vulnerable to LDAP Injection in multiple methods. A low-privileged remote attacker can inject crafted LDAP syntax into ID-based search parameters, potentially resulting in unauthorized LDAP queries and arbitrary directory operations. This issue was fixed in PAC4J versions 4.5.10, 5.7.10 and 6.4.1
Frequently asked questions
- What is CVE-2026-40459?
- PAC4J is vulnerable to LDAP Injection in multiple methods. A low-privileged remote attacker can inject crafted LDAP syntax into ID-based search parameters, potentially resulting in unauthorized LDAP queries and arbitrary directory operations. This issue was fixed in PAC4J versions 4.5.10, 5.7.10 and 6.4.1
- How severe is CVE-2026-40459?
- CVE-2026-40459 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-40459 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-40459?
- CVE-2026-40459 affects Pac4j. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-40459?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-40459 have an EU (EUVD) identifier?
- Yes. CVE-2026-40459 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-23423.
- When was CVE-2026-40459 published?
- CVE-2026-40459 was published on 2026-04-17 and last updated on 2026-06-17.
References
- https://cert.pl/en/posts/2026/04/CVE-2026-40458/
- https://www.pac4j.org/blog/security-advisory-pac4j-core-and-ldap.html
Affected products (1)
- cpe:2.3:a:pac4j:pac4j:*:*:*:*:*:*:*:*
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