CVE-2026-9087: Red Hat build of Keycloak 26.4 · Insecure Direct Object Reference
Affects Red Hat build of Keycloak 26.4Source CVE Database V5
Not known to be exploited · CVSS 6.4 Medium · fixed in Red Hat package updates : update Red Hat build of Keycloak 26.4 when convenient.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.6.3
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Red Hatredhat/keycloakpkg:rpm/redhat/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 updated Keycloak 26.6.3 images that address CVE-2026-9087 along with other security issues. Users of Red Hat build of Keycloak should update to version 26.6.3 or later as provided in the Red Hat advisories RHSA-2026:25097 and RHSA-2026:25098. Before updating, back up existing installations including applications, configuration files, and databases. No alternative workarounds or mitigations are specified. Patch status is confirmed by the vendor advisories. There are no known exploits in the wild at this time.
Description
A flaw was found in Keycloak. The cross-session verification proof is keyed only by (local userId, idpAlias) and is not bound to the upstream identity that was actually verified, so a second upstream account on the same IdP can consume it and get linked to the victim's local account.
References
- access.redhat.com/errata/RHSA-2026:25097 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:25098 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30049 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:30050 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-9087 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2480172 (opens in a new tab)