PT-2026-42199 · Red Hat · Keycloak

Published 2026-05-20 · Updated 2026-06-26 · CVE-2026-9087

Positive Technologies (AI Summary)

CVSS v3.1

8.1

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Keycloak (affected versions not specified)

Description A flaw exists where the cross-session verification proof is keyed only by the userId and idpAlias and is not bound to the upstream identity that was actually verified. This allows a second upstream account on the same Identity Provider (IdP) to consume the proof and link itself to the victim's local account.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

IDOR

Weakness Enumeration

CWE-639

Related Identifiers

CVE-2026-9087

GHSA-M6QJ-3MPP-57V8

Affected Products

Keycloak

References · 15

• https://access.redhat.com/security/cve/CVE-2026-9087 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:30050 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:30049 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-m6qj-3mpp-57v8 · Vendor Advisory
• https://access.redhat.com/errata/RHSA-2026:25097 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-9087 · Security Note
• https://access.redhat.com/errata/RHSA-2026:25098 · Vendor Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=2480172 · Vendor Advisory
• https://github.com/keycloak/keycloak · Note
• https://github.com/keycloak/keycloak/commit/37dabf59d0b5ca3e5b3b272bcd3b2580e67b94dd · Note
• https://github.com/keycloak/keycloak/releases/tag/26.6.3 · Note
• https://t.me/cveNotify/166958 · Telegram Post
• https://t.me/cveNotify/176380 · Telegram Post
• https://t.me/cveNotify/176653 · Telegram Post
• https://t.me/cveNotify/176477 · Telegram Post