Vulnerability-Lookup

GHSA-PCF4-9G97-7CPF

Vulnerability from github – Published: 2026-08-04 06:31 – Updated: 2026-08-04 06:31

Details

A flaw was found in the backchannel logout endpoint of the keycloak-services component, which is part of the Red Hat Build of Keycloak. This component handles authentication and session management for applications. The issue occurs when an OIDC identity provider is configured to skip signature validation. In this specific setup, the system incorrectly accepts logout requests that have no cryptographic signature. An attacker who knows certain technical details about a user's session can use this flaw to force that user to be logged out, potentially disrupting their work.

Severity

3.7 (Low)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

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  "aliases": [
    "CVE-2026-18569"
  ],
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  "id": "GHSA-pcf4-9g97-7cpf",
  "modified": "2026-08-04T06:31:36Z",
  "published": "2026-08-04T06:31:36Z",
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-18569"
    },
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    },
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      "type": "WEB",
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      "type": "CVSS_V3"
    }
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}

CVE-2026-18569 (GCVE-0-2026-18569)

Vulnerability from cvelistv5 – Published: 2026-08-04 05:13 – Updated: 2026-08-04 14:40

Title

Keycloak-services: keycloak-services: oidc backchannel logout accepts unsigned forged logout tokens

Summary

Severity

3.7 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-347 - Improper Verification of Cryptographic Signature

Assigner

redhat

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-18569	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2509755	issue-trackingx_refsource_REDHAT

Impacted products

4 products

Vendor	Product	Version
Red Hat	Red Hat Build of Keycloak	cpe:/a:redhat:build_keycloak:
Red Hat	Red Hat Data Grid 8	cpe:/a:redhat:jboss_data_grid:8
Red Hat	Red Hat JBoss Enterprise Application Platform Expansion Pack	cpe:/a:redhat:jbosseapxp
Red Hat	Red Hat Single Sign-On 7	cpe:/a:redhat:red_hat_single_sign_on:7

Date Public

2026-07-31 10:18

Credits

Red Hat would like to thank Paul Bottinelli (Trail of Bits) for reporting this issue.

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-PCF4-9G97-7CPF

CVE-2026-18569 (GCVE-0-2026-18569)

Tags

Sightings

Nomenclature