CVE-2026-16100: Red Hat build of Keycloak 26.6 · Unthrottled Resource Allocation
Affects Red Hat build of Keycloak 26.6Source CVE Database V5
Not known to be exploited · CVSS 6.5 Medium.
Data as of 3 Nov 2026, 10:57 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 46% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 5 Aug 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 3 Nov 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 26.6.5 | 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– |
AI-suggested
Users should monitor Red Hat's security advisories for updates or patches addressing this vulnerability. Until a fix is available, limiting access to users with account management permissions and disabling metrics if feasible may reduce exposure.
Description
A flaw was found in the user-event metrics recording of Keycloak. When metrics are enabled, the system records raw error messages from failed account operations as Prometheus metric labels. Because these error messages can include user-supplied input like nonexistent client IDs, an authenticated user can create a massive number of unique metric entries, eventually exhausting system memory and causing the service to crash or become unavailable.