CVE-2026-4874: Red Hat build of Keycloak 26.4 · Server-Side Request Forgery (SSRF)
Affects Red Hat build of Keycloak 26.4Source CVE Database V5
Not known to be exploited · CVSS 3.1 Low.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% 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:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Mar 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 26.4 | Affected– | Fixed in– |
| Red HatRed Hat build of Keycloak 26.4 | Affected– | Fixed in– |
| Red HatRed Hat build of Keycloak 26.4.13 | 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 26.6.3 | Affected– | Fixed in– |
AI-suggested
Red Hat has released updated Keycloak 26.6.3 images that address this vulnerability. Users should back up their existing installations, including configurations and databases, and upgrade to the fixed version 26.6.3 as provided by Red Hat. No other temporary or workaround mitigations are specified in the advisory. Patch status is confirmed by the vendor advisory. Users should follow Red Hat’s official update procedures to remediate this issue.
Description
A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.
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-2026-4874 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2451611 (opens in a new tab)