CVE-2026-7307

Keycloak: keycloak: denial of service via specially crafted saml input

HIGH
7.5
CVSS Score
Published: May 19, 2026 at 10:52 AM UTC
Updated: October 26, 2026 at 01:10 PM UTC
3 products affected across 2 vendorsBuild of KeycloakKeycloakSingle Sign on

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Severity
HIGH7.5
Exploit prediction
EPSS 0.9%
SSVC
No known exploit

Description

A flaw was found in Keycloak. A remote, unauthenticated attacker can send a specially crafted XML input to the Security Assertion Markup Language (SAML) endpoint. This malicious input can cause high CPU usage and worker thread starvation, leading to a Denial of Service (DoS) where the server becomes unavailable.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

26.4 ≤ v < 26.4.12
Vendor states this is fixed in 26.2-21 (unaffected)
Vendor states this is fixed in 26.2.16 (unaffected)
Vendor states this is fixed in 26.2.16-1 (unaffected)
Vendor states this is fixed in 26.4-17 (unaffected)
Vendor states this is fixed in 26.4.12 (unaffected)
Vendor states this is fixed in 26.4.12-1 (unaffected)
All versions
All versions7
Vendor states this is fixed in 0:18.0.20-1.redhat_00001.1.el7sso (unaffected)
Vendor states this is fixed in 0:18.0.20-1.redhat_00001.1.el8sso (unaffected)
Vendor states this is fixed in 0:18.0.20-1.redhat_00001.1.el9sso (unaffected)

References (12)

VDB Entryx_refsource_REDHATVendor Advisory
Source: cverecord
https://access.redhat.com/security/cve/CVE-2026-7307
Issue Trackingx_refsource_REDHATVendor Advisory
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2476526
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:19594
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:19597
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:19595
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:19596
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:76132

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-1286

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