Medium severity · published Mar 18, 2026
CVE-2026-4366
Keycloak-services: blind server-side request forgery (ssrf) via http redirect handling in keycloak
5.8
CVSS
0.2%
EPSS
No
On KEV
Description
A flaw was identified in Keycloak, an identity and access management solution, where it improperly follows HTTP redirects when processing certain client configuration requests. This behavior allows an attacker to trick the server into making unintended requests to internal or restricted resources. As a result, sensitive internal services such as cloud metadata endpoints could be accessed. This issue may lead to information disclosure and enable attackers to map internal network infrastructure.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RH
Red Hat Build of Keycloak · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform 8 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat JBoss Enterprise Application Platform Expansion Pack · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat Single Sign-On 7 · Red Hat
All versions, or not specified · source: vendor
RH
Red Hat build of Keycloak 26.4 · Red Hat
All versions, or not specified · source: vendor
BO
Build OF Keycloak · Redhat
All versions, or not specified · source: NVD
JE
Jboss Enterprise Application Platform · Redhat
8.0.0 · source: NVD
JE
Jboss Enterprise Application Platform Expansion Pack · Redhat
All versions, or not specified · source: NVD
SS
Single Sign-on · Redhat
7.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4366
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4366
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:19596
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:19597
Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4366
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=2448543
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