CVE-2026-87853
Sssd: sssd: idp authentication prefix comparison allows cross-user impersonation
HIGH 7.5
En bref
- Source
- NVD
- EPSS
- EPSS 0.33 % · centile 26 ()
- État
- PUBLISHED
- Publiée
- Mise à jour
- Attribuée par
- redhat
- Statut NVD
- Awaiting Analysis
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.
Faiblesses (CWE)
Références
Scores
| Version | Score | Vecteur | Évalué par |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H | redhat |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H | NVD · secalert@redhat.com (Secondary) |
Références européennes
- ENISA EUVD · EUVD-2026-75084
- GCVE · GCVE-0-2026-87853
Produits affectés
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |