CVE-2026-82461
pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token
CVE-2026-82461 is a high vulnerability (CVSS 8.6) in Pac4j, published August 29, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.32%, the 24th percentile. No source names a fixed version.
- Severity
- 8.6 HighCVSS 4.0, CVE List
- Exploit chance
- 0.32%EPSS, 24th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- None
Exploit likelihood
Affected products
What each source reports
CVE List Score used
pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token
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.
- Record
CVE-2026-82461- CVSS 4.0
- 8.6 High
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 - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
EUVDEUVD-2026-68118
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.
- Record
EUVD-2026-68118- CVSS 4.0
- 8.6 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-4w24-77rp-687q
pac4j-oidc before 6.5.6 fails to verify access token signatures, issuers, audiences, or expiry...
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.
- Record
GHSA-4w24-77rp-687q- CVSS 4.0
- 8.6 High
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/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 - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-82461- CVSS 4.0
- 8.6 High
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/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 - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - Weakness
- CWE-347
- Updated
- 2026-11-02
OSV
pac4j-oidc before 6.5.6 Privilege Escalation via Unverified Keycloak Access Token
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.
- Record
CVE-2026-82461- CVSS 4.0
- 8.6 High
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 - Weakness
- CWE-347
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
github.com/pac4j/pac4j/commit/2270c3ff70e93cc43831e75702acd5135531237e
pac4j.org/blog/security-advisory-pac4j-core-oidc-saml.html
vulncheck.com/advisories/pac4j-oidc-before-6.5.6-privilege-escalation-via-unverified-keycloak-access-token
nvd.nist.gov/vuln/detail/CVE-2026-82461