CVE-2026-40459LDAP Injection in PAC4J

8.7HighCVSS base score
0.61%Exploitation in 30 daysEPSS · top 50% of all CVEs
NoKnown exploitednot in CISA's KEV catalog
NonePublic exploitsnone known yet

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

Timeline

2026
13 Apr 2026
13 Apr 2026
ID reserved
By CERT-PL
17 Apr 20264 days later
17 Apr 2026· 4 days later
Published

Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.

Scores

CVSS scores of CVE-2026-40459, by who scored it
Scored by	CVSS	Score	Vector
CERT-PLCNA (assigner)	4.0	High8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
NVDNVD · Analyzed	4.0	High8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/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

EPSS (exploitation in 30 days): 0.61% · top 50% of all CVEs (12 Nov 2026)
CISA SSVC: Exploitation: none · Automatable: no · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.

Affected products

PAC4J · PAC4J
- affected 4.0 – < 4.5.10
- affected 5.0 – < 5.7.10
- affected 6.0 – < 6.4.1

References2

https://cert.pl/en/posts/2026/04/CVE-2026-40458/ (opens in a new tab)third-party-advisory
https://www.pac4j.org/blog/security-advisory-pac4j-core-and-ldap.html (opens in a new tab)vendor-advisory

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

[![CVE-2026-40459](https://cveledger.app/badge/CVE-2026-40459.svg)](https://cveledger.app/cve/CVE-2026-40459)

Record last updated 17 Apr 2026, 13:54 UTC.