CVE-2026-37981: Red Hat build of Keycloak 26.4 · Insufficient Granularity of Access Control
Affects Red Hat build of Keycloak 26.4Source CVE Database V5
Not known to be exploited · CVSS 4.3 Medium : upgrade Red Hat build of Keycloak 26.4 to 26.4.12 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.4.12
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 19 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade org.keycloak/keycloak to 26.4.12.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Mavenorg.keycloak/keycloakpkg:maven/org.keycloak/keycloakOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released an updated package, Keycloak 26.4.12, which addresses this vulnerability along with several others. Users should back up their existing installations, including applications, configuration files, and databases, before applying the update. Applying the official update fully mitigates this vulnerability. No additional mitigations are specified or required beyond applying the update.
Description
CVE-2026-37981 is a medium severity vulnerability in Red Hat build of Keycloak 26.4 that involves broken access control in the Account Resources user lookup endpoint. It allows a remote authenticated user who owns at least one User-Managed Access (UMA) resource to enumerate and harvest personally identifiable information (PII) of all users in the realm by sending crafted requests with arbitrary usernames or email values. Red Hat has released an updated package, Keycloak 26.4.12, that addresses this vulnerability along with others. Users are advised to back up their installations and apply the update. No known exploits are reported in the wild at this time.