CVE-2026-87853
medium
Red Hat CVSS v3 Base Score
7.5
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Characteristics
Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Confidentiality
High
Integrity
High
Availability
High
Published: September 9, 2026 (1 days ago)
Last Modified: September 9, 2026
Vendor: Red Hat
Source: REDHAT
Vulnerability Report
Generated by CyberWatcher
Description
A flaw was found in SSSD's IdP authentication provider. The eval_access_token_buf() function compares the OIDC subject identifier using strncmp() with the authenticated user's identifier length, performing a prefix comparison instead of an exact match. An attacker whose IdP identifier is a strict prefix of a target user's identifier can authenticate as the target user.
CWE
CWE-187Affected Products
Red Hat Enterprise Linux 10Red Hat Enterprise Linux 6Red Hat Enterprise Linux 7Red Hat Enterprise Linux 8Red Hat Enterprise Linux 9Red Hat OpenShift Container Platform 4