---
cve: "CVE-2026-82461"
severity: "HIGH"
cvss: 8.6
epss: "19%"
vendor: "pac4j"
kev: false
exploited: false
published: "2026-08-29 17:17:58"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-02T16:49:44+02:00"
---

# CVE-2026-82461

> 8.6 HIGH · 🧪 PoC

## Beschreibung

pac4j-oidc before 6.5.6 fails to verify access token signatures, issuers, audiences, or expiry when extracting Keycloak realm and client roles. Attackers can forge access tokens with administrative roles paired with valid ID tokens to bypass authorization checks in applications relying on pac4j role validation.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 0ce4586f0526cb94d1e2bb6623c416db9b4dc2a3 (Commit)

## Referenzen

- <https://github.com/pac4j/pac4j/commit/2270c3ff70e93cc43831e75702acd5135531237e>
- <https://www.pac4j.org/blog/security-advisory-pac4j-core-oidc-saml.html>
- <https://github.com/pac4j/pac4j/blob/pac4j-parent-6.5.5/pac4j-oidc/src/main/java/org/pac4j/oidc/authorization/generator/KeycloakRolesAuthorizationGenerator.java>
- <https://github.com/pac4j/pac4j>
- <https://www.vulncheck.com/advisories/pac4j-oidc-before-6.5.6-privilege-escalation-via-unverified-keycloak-access-token>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-82461) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_