CVE-2023-6787

Keycloak: session hijacking via re-authentication

State: Published
Severity: 6.5 Medium
Published: Apr 25, 2024
Updated: Nov 11, 2025
Reserved: Dec 13, 2023

Description

A flaw was found in Keycloak that occurs from an error in the re-authentication mechanism within org.keycloak.authentication. This flaw allows hijacking an active Keycloak session by triggering a new authentication process with the query parameter "prompt=login," prompting the user to re-enter their credentials. If the user cancels this re-authentication by selecting "Restart login," an account takeover may occur, as the new session, with a different SUB, will possess the same SID as the previous session.

Scores

CVSS	Score	Vector	Source
3.1	6.5 Medium	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N	redhat

Weaknesses

CWE-287 Improper Authentication

Affected Products

Product	Versions
keycloak	before 22.0.10Affected before 24.0.3Affected
Red Hat build of Keycloak 22Red Hat	22.0.10-1 and laterNot affected
Red Hat build of Keycloak 22Red Hat	22-13 and laterNot affected
Red Hat build of Keycloak 22Red Hat	22-16 and laterNot affected
Red Hat build of Keycloak 22.0.10Red Hat
Red Hat Single Sign-On 7Red Hat

References

RHSA-2024:1867vendor-advisory
RHSA-2024:1868vendor-advisory
https://access.redhat.com/security/cve/CVE-2023-6787vdb-entry
RHBZ#2254375issue-tracking
https://github.com/keycloak/keycloak/security/advisories/GHSA-c9h6-v78w-52wj

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