Vulnerability-Lookup

GHSA-H87Q-RX56-87WM

Vulnerability from github – Published: 2026-09-16 18:32 – Updated: 2026-09-16 18:32

Details

A flaw was found in the first-broker-login flow of the keycloak-services component. This component handles the initial authentication and account linking when a user logs in via an external identity provider. The issue allows an attacker to register a matching username on an external provider to trigger a collision in Keycloak, which results in the legitimate user being locked out of their account.

Severity

5.3 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-19607"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-287"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-16T16:17:06Z",
    "severity": "MODERATE"
  },
  "details": "A flaw was found in the first-broker-login flow of the keycloak-services component. This component handles the initial authentication and account linking when a user logs in via an external identity provider. The issue allows an attacker to register a matching username on an external provider to trigger a collision in Keycloak, which results in the legitimate user being locked out of their account.",
  "id": "GHSA-h87q-rx56-87wm",
  "modified": "2026-09-16T18:32:03Z",
  "published": "2026-09-16T18:32:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-19607"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:68276"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:68277"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:68278"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:68280"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-19607"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2514529"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-19607 (GCVE-0-2026-19607)

Vulnerability from cvelistv5 – Published: 2026-09-16 15:46 – Updated: 2026-09-16 18:35

Title

Keycloak-services: keycloak-services: broker-originated username collision causes account lockout

Summary

Severity

5.3 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-16 18:25 UTC

CWE

CWE-287 - Improper Authentication

Assigner

redhat redhat root

References

6 references

URL	Tags
https://access.redhat.com/errata/RHSA-2026:68276	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:68277	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:68278	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:68280	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-19607	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2514529	issue-trackingx_refsource_REDHAT

Impacted products

7 products

Vendor	Product	Version
Red Hat	Red Hat build of Keycloak 26.4	Unaffected: 26.4.16-2 , < * (rpm) cpe:/a:redhat:build_keycloak:26.4::el9
Red Hat	Red Hat build of Keycloak 26.4	Unaffected: 26.4-26 , < * (rpm) cpe:/a:redhat:build_keycloak:26.4::el9
Red Hat	Red Hat build of Keycloak 26.4.16	cpe:/a:redhat:build_keycloak:26.4::el9
Red Hat	Red Hat build of Keycloak 26.6	Unaffected: 26.6.7-3 , < * (rpm) cpe:/a:redhat:build_keycloak:26.6::el9
Red Hat	Red Hat build of Keycloak 26.6	Unaffected: 26.6-20 , < * (rpm) cpe:/a:redhat:build_keycloak:26.6::el9
Red Hat	Red Hat build of Keycloak 26.6.7	cpe:/a:redhat:build_keycloak:26.6::el9
Red Hat	Red Hat Single Sign-On 7	cpe:/a:redhat:red_hat_single_sign_on:7

Date Public

2026-09-16 13:01

Credits

Red Hat would like to thank Anurag Mondal (NetSPI) 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.
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.