CVE-2026-2575 (GCVE-0-2026-2575)

Vulnerability from cvelistv5 – Published: 2026-03-18 03:19 – Updated: 2026-03-18 13:34
VLAI?
Title
Keycloak: keycloak: denial of service due to excessive samlrequest decompression
Summary
A flaw was found in Keycloak. An unauthenticated remote attacker can trigger an application level Denial of Service (DoS) by sending a highly compressed SAMLRequest through the SAML Redirect Binding. The server fails to enforce size limits during DEFLATE decompression, leading to an OutOfMemoryError (OOM) and subsequent process termination. This vulnerability allows an attacker to disrupt the availability of the service.
Severity ?
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
References
https://access.redhat.com/errata/RHSA-2026:3947 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:3948 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-2575 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2440149 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat build of Keycloak 26.4 Unaffected: 26.4.10-1 , < * (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: 26.4-12 , < * (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: 26.4-12 , < * (rpm)
    cpe:/a:redhat:build_keycloak:26.4::el9
 Create a notification for this product.
    Red Hat Red Hat build of Keycloak 26.4.10     cpe:/a:redhat:build_keycloak:26.4::el9
 Create a notification for this product.
Date Public ?
2026-02-16 08:08
Credits
Red Hat would like to thank Sho Odagiri (GMO Cybersecurity by Ierae, Inc.) for reporting this issue.
Show details on NVD website
To clipboard 

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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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