Org.keycloak/keycloak-services: session fixation in oidc login flow that can lead to account takeover

Summary

CVE	CVE-2026-7507
State	PUBLISHED
Assigner	redhat
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-05-19 12:16:19 UTC
Updated	2026-06-03 19:51:26 UTC
Description	A session fixation vulnerability was found in Keycloak's login-actions endpoints. An unauthenticated attacker could exploit this flaw by pre-creating an authentication session and tricking a victim into visiting a maliciously crafted link. By leveraging the /login-actions/restart endpoint—which processes session handles without adequate CSRF protection or cookie ownership validation—an attacker can reset the authentication flow state. This causes Single Sign-On (SSO) to authenticate the victim transparently upon clicking the link, allowing the attacker to hijack the required-action form without needing the victim's credentials. A successful exploit could lead to complete account takeover, including highly privileged administrative accounts.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from [email protected]

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

EPSS: 0.000210000 probability, percentile 0.059720000 (date 2026-06-03)

Problem Types: CWE-290 | CWE-290 Authentication Bypass by Spoofing

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Secondary	7.5	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H`
3.1	CNA	CVSS	7.5	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H`

CVSS v3.1 Breakdown

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

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

NVD Known Affected Configurations (CPE 2.3)

Type	Vendor	Product	Version	Update	Edition	Language
Application	Redhat	Build Of Keycloak	All	All	All	All

Vendor Declared Affected Products

Source	Vendor	Product	Version	Platforms
CNA	Red Hat	Red Hat Build Of Keycloak 26.2	unaffected 26.2.16-1 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.2	unaffected 26.2-21 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.2	unaffected 26.2-21 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.2.16	Not specified	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4.12-1 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4-17 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4	unaffected 26.4-17 * rpm	Not specified
CNA	Red Hat	Red Hat Build Of Keycloak 26.4.12	Not specified	Not specified

References

Reference	Source	Link	Tags
access.redhat.com/errata/RHSA-2026:19594	[email protected]	access.redhat.com	Vendor Advisory
access.redhat.com/errata/RHSA-2026:19595	[email protected]	access.redhat.com	Vendor Advisory
access.redhat.com/errata/RHSA-2026:19596	[email protected]	access.redhat.com	Vendor Advisory
access.redhat.com/errata/RHSA-2026:19597	[email protected]	access.redhat.com	Vendor Advisory
bugzilla.redhat.com/show_bug.cgi	[email protected]	bugzilla.redhat.com	Vendor Advisory
access.redhat.com/security/cve/CVE-2026-7507	[email protected]	access.redhat.com	Vendor Advisory
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Red Hat would like to thank Hacking Team (Calif.io) for reporting this issue. (en)

Additional Advisory Data

Source	Time	Event
CNA	2026-04-30T14:57:56.441Z	Reported to Red Hat.
CNA	2026-05-19T10:51:31.418Z	Made public.

Workarounds

CNA: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

There are currently no legacy QID mappings associated with this CVE.