Redhat Build Of Keycloak
CVE-2026-9796
A flaw was found in Keycloak. An authenticated administrator with the `manage-clients` role can exploit a Time-of-check to time-of-use (TOCTOU) vulnerability in the name-based admin role checks. This allows the attacker to escalate their privileges to `realm-admin` for all users within the realm, granting them extensive control over the system. The composite role relationship persists even after the attacker's own permissions are revoked and across system reboots.
What this means for your business
- It affects Redhat Build Of Keycloak. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, with an administrator login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 12% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Redhat Build Of Keycloak, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 6.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N- Weakness
- CWE-367
- Assigned by
- secalert@redhat.com
Dates
- Published
- 2026-05-28
- Last modified
- 2026-09-15
- Sources
- NVD
Affected products
- Redhat Build Of Keycloakall versions
As listed in the NVD configuration data. Not a statement about your estate.