CVE-2026-107602 (GCVE-0-2026-107602)

Vulnerability from cvelistv5 – Published: 2026-11-05 16:04 – Updated: 2026-11-06 19:55
VLAI
Title
Keycloak-services: keycloak-services: unauthenticated cpu exhaustion via saml 1.1 keyinfo infinite loop
Summary
A flaw was found in the SAML 1.1 XML parsing logic of Keycloak, an open-source identity and access management solution. The issue occurs when the parser encounters unexpected elements within a security token's key information section, causing the processing thread to enter an infinite loop. An unauthenticated remote attacker could exploit this by sending specially crafted requests, leading to 100% CPU usage and a total denial of service that requires a server restart to resolve.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-835 - Loop with Unreachable Exit Condition
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1131 records in the last 180 days details
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:95759 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:95760 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:95761 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:95762 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-107602 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2547937 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.17-2 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-29 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4-30 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.4.17     cpe:/a:redhat:build_keycloak:26.4::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.6 Unaffected: 26.6.8-2 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.6::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.6 Unaffected: 26.6-24 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.6::el9
Create a notification for this product.
Red Hat Red Hat build of Keycloak 26.6.8     cpe:/a:redhat:build_keycloak:26.6::el9
Create a notification for this product.
Red Hat Red Hat Single Sign-On 7     cpe:/a:redhat:red_hat_single_sign_on:7
Create a notification for this product.
Date Public
2026-11-05 00:00
Credits
Red Hat would like to thank Animesh Roy for reporting this issue.
Show details on NVD website
To clipboard 

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How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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