CVE-2026-87853

Estado: Pendiente de análisisAlta (7.5)—

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.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.48%
Percentil entre todas las CVEs puntuadas: 39
Fecha de la puntuación: 6/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement75 %
Impacto principalT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access85 %
Impacto secundarioT1556.002 Password Filter DLLdefense impairment · persistence · credential access65 %

Vulnerabilidad de autenticación en SSSD (servicio de red) accesible localmente o en red adyacente (PR:L); permite suplantación de usuario. Impacto: acceso con identidad falsa (T1078.001) y manipulación de IdP (T1556.002).

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Vulnerability Scanning Threat Intelligence Program Privileged Account Management Password Policies Operating System Configuration Network Segmentation

Tecnologías afectadas (1)

⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.

Sssd — Sssd^AI

CWE

CWE-187

Referencias

JSON original (NVD)

Mostrar

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          "options": [
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