GHSA-p3v8-fm5p-v84h
Keycloak has an Improper Verification of Cryptographic Signature issue
At a glance
- Published
- Updated
- CVE
- CVE-2026-9793
- CVSS_V3
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Description
A flaw was found in Keycloak. When a JSON Web Encryption (JWE) encrypted request object is submitted, Keycloak may incorrectly process unsigned claims if the decrypted content is raw JSON, bypassing the configured signature policy. This allows a remote attacker to submit unauthorized claims, leading to a compromise of data integrity within the OpenID Connect (OIDC) authorization flow. While a redirect URI allowlist acts as a compensating control, this vulnerability violates OIDC Core and Financial-grade API (FAPI) signing requirements.
Affected packages
| Package | Versions |
|---|---|
| Maven · org.keycloak:keycloak-services | introduced 0, last affected 26.6.4 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2026-9793 ADVISORY
- https://github.com/keycloak/keycloak/issues/49429 WEB
- https://access.redhat.com/errata/RHSA-2026:50846 WEB
- https://access.redhat.com/errata/RHSA-2026:50847 WEB
- https://access.redhat.com/errata/RHSA-2026:50848 WEB
- https://access.redhat.com/errata/RHSA-2026:50849 WEB
- https://access.redhat.com/security/cve/CVE-2026-9793 WEB
- https://bugzilla.redhat.com/show_bug.cgi?id=2482460 WEB
- https://github.com/keycloak/keycloak PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |