CVE-2026-4634A flaw was found in Keycloak.
Updated under an hour ago ()
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It affects redhat build_of_keycloak. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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A flaw was found in Keycloak. An unauthenticated attacker can exploit this vulnerability by sending a specially crafted POST request with an excessively long scope parameter to the OpenID Connect (OIDC) token endpoint. This leads to high resource consumption and prolonged processing times, ultimately resulting in a Denial of Service (DoS) for the Keycloak server.
- CVSS
- 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- CWE-1050
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Modified
- Record last updated
- Oct 6, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
redhat build_of_keycloak redhat:build_of_keycloak | all versions; 26.2; 26.2.15; 26.4; 26.4.11 | NVD |
References
- https://access.redhat.com/errata/RHSA-2026:6475vendor-advisory
- https://access.redhat.com/errata/RHSA-2026:6476vendor-advisory
- https://access.redhat.com/errata/RHSA-2026:6477vendor-advisory
- https://access.redhat.com/errata/RHSA-2026:6478vendor-advisory
- https://access.redhat.com/errata/RHSA-2026:76128
- https://access.redhat.com/errata/RHSA-2026:76129
- https://access.redhat.com/errata/RHSA-2026:76130
- https://access.redhat.com/errata/RHSA-2026:76132
- https://access.redhat.com/errata/RHSA-2026:76134
- https://access.redhat.com/security/cve/CVE-2026-4634vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2450250issue-tracking, vendor-advisory
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4634.json
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.