Vulnerability-Lookup

GHSA-FGHP-HCWH-75J2

Vulnerability from github – Published: 2026-08-06 09:30 – Updated: 2026-08-06 09:30

Details

A flaw was found in the SAML broker component of Keycloak, an identity and access management solution. When configured as a SAML broker using the IdP-Initiated flow, Keycloak fails to enforce the OneTimeUse condition in SAML assertions. This allows an attacker who captures a valid, unused assertion to replay it multiple times. Successful exploitation could allow an attacker to hijack a user's session and gain unauthorized access to the system as that user.

Severity

6.4 (Medium)


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

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  "affected": [],
  "aliases": [
    "CVE-2026-18967"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-294"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-06T07:16:29Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in the SAML broker component of Keycloak, an identity and access management solution. When configured as a SAML broker using the IdP-Initiated flow, Keycloak fails to enforce the OneTimeUse condition in SAML assertions. This allows an attacker who captures a valid, unused assertion to replay it multiple times. Successful exploitation could allow an attacker to hijack a user\u0027s session and gain unauthorized access to the system as that user.",
  "id": "GHSA-fghp-hcwh-75j2",
  "modified": "2026-08-06T09:30:30Z",
  "published": "2026-08-06T09:30:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-18967"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-18967"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2511604"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-18967 (GCVE-0-2026-18967)

Vulnerability from cvelistv5 – Published: 2026-08-06 05:33 – Updated: 2026-08-06 17:31

Title

Keycloak-services: keycloak-services: saml onetimeuse assertion replay in idp-initiated broker flow

Summary

Severity

6.4 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-06 17:25 UTC

CWE

CWE-294 - Authentication Bypass by Capture-replay

Assigner

redhat redhat root Scorecard

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-18967	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2511604	issue-trackingx_refsource_REDHAT

Impacted products

3 products

Vendor	Product	Version
Red Hat	Red Hat Build of Keycloak	cpe:/a:redhat:build_keycloak:
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 14:42

Credits

Red Hat would like to thank Lidor Vasker for reporting this issue.

Show details on NVD website

JSON

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                  },
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                  }
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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.

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.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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GHSA-FGHP-HCWH-75J2

CVE-2026-18967 (GCVE-0-2026-18967)

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