Description
A flaw was found in Keycloak. When the logging format is configured to a verbose, user-supplied pattern (such as the pre-defined 'long' pattern), sensitive headers including Authorization and Cookie are disclosed to the logs in cleartext. An attacker with read access to the log files can extract these credentials (e.g., bearer tokens, session cookies) and use them to impersonate users, leading to a full account compromise.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Red Hat | Red Hat build of Keycloak 26.4.2 | — | — |
| Red Hat | Red Hat Build of Keycloak | — | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | keycloak-26.4-iamguarded-compat | No fix yet | — |
| Wolfi rolling | keycloak-26.5 +1 | 26.5.6-r3 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | org.keycloak:keycloak-quarkus-server | < 26.5.6 | 26.5.6 | GHSA-gv3v-2cpp-3pmq |
Advisories 1
- WID-SEC-2026-0394 Keycloak: Mehrere Schwachstellen ermöglichen Offenlegung von Informationen BSI CERT-Bund (WID) · Apr 6, 2026
References
- RHEA-2025:19385 vendor-advisory
- RHEA-2025:19386 vendor-advisory
- https://access.redhat.com/security/cve/CVE-2025-11537 vdb-entry
- RHBZ#2402616 issue-tracking