CVE-2026-18215: Red Hat build of Keycloak 26.6 · Improper Authentication
Affects Red Hat build of Keycloak 26.6Source CVE Database V5
Not known to be exploited · CVSS 6.8 Medium.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 34% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 31 Jul 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 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red HatRed Hat build of Keycloak 26.6 | Affected– | Fixed in– |
| Red HatRed Hat build of Keycloak 26.6 | Affected– | Fixed in– |
| Red HatRed Hat build of Keycloak 26.6.7 | Affected– | Fixed in– |
| Red HatRed Hat Data Grid 8 | Affected– | Fixed in– |
| Red HatRed Hat JBoss Enterprise Application Platform Expansion Pack | Affected– | Fixed in– |
| Red HatRed Hat Single Sign-On 7 | Affected– | Fixed in– |
Description
Keycloak provides a way to let users log in using Microsoft accounts while restricting access to a specific organization (tenant). A flaw was discovered where this restriction is ignored when using the token exchange feature. This means an attacker with a valid Microsoft token from a completely different organization could gain access to the Keycloak realm, potentially accessing sensitive data or performing unauthorized actions.