VDB
CVE-2026-87853
CVE-2026-87853
PUBLISHED
CVSS 7.5 HIGH
Reported by redhat · Published September 9, 2026
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.
Risk Scores
CVSS 3.1
7.5
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | 0:2.12.0-3.el10_2.2 |
| Red Hat | Red Hat Enterprise Linux 6 | |
| Red Hat | Red Hat Enterprise Linux 7 | |
| Red Hat | Red Hat Enterprise Linux 8 | |
| Red Hat | Red Hat Enterprise Linux 9 | |
| Red Hat | Red Hat OpenShift Container Platform 4 | |
| Red Hat | Red Hat OpenShift Container Platform 4 | |
| Red Hat | Red Hat OpenShift Container Platform 4 | |
| Red Hat | Red Hat Enterprise Linux 6 | |
| Red Hat | Red Hat Enterprise Linux 7 | |
| Red Hat | Red Hat Enterprise Linux 10 | 0:2.12.0-3.el10_2.2 |
| Red Hat | Red Hat Enterprise Linux 8 | |
| Red Hat | Red Hat Enterprise Linux 9 | |
| Red Hat | Red Hat OpenShift Container Platform 4 |
Timeline
- Sep 9, 2026 Coalition ESS Score
- Sep 9, 2026 CVE Published
- Sep 10, 2026 EPSS Score
- Sep 12, 2026 EPSS Score
- Sep 16, 2026 EPSS Score
- Sep 18, 2026 EPSS Score
- Sep 24, 2026 EPSS Score
- Sep 26, 2026 EPSS Score
- Sep 30, 2026 EPSS Score
- Oct 2, 2026 EPSS Score
- Oct 6, 2026 EPSS Score
- Oct 8, 2026 EPSS Score
References
- RHSA-2026:77534 vendor-advisoryx_refsource_REDHAT
- vdb-entryx_refsource_REDHAT
- RHBZ#2530888 issue-trackingx_refsource_REDHAT