CVE-2026-20896

Estado: AplazadaCrítica (9.8)—

Gitea Docker image versions up to and including 1.26.2 use REVERSE_PROXY_TRUSTED_PROXIES=* by default, allowing any source IP to impersonate a user when reverse-proxy authentication headers such as X-WEBAUTH-USER are enabled.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 2.76%
Percentil entre todas las CVEs puntuadas: 86
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access95 %
Impacto principalT1078.001 Default Accountsstealth · persistence · privilege escalation · initial access90 %
Impacto secundarioT1556.008 Network Provider DLLdefense impairment · persistence · credential access85 %

Acceso remoto sin autenticación (AV:N/PR:N/UI:N) a aplicación expuesta Gitea; suplantación de usuario mediante headers de proxy permite acceso como cualquier usuario, incluido admin, sin credenciales válidas.

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 Restrict Registry Permissions 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.

Gitea — Docker Image^AI

CWE

CWE-284

Referencias

JSON original (NVD)

Mostrar

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  "id": "CVE-2026-20896",
  "cveTags": [],
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          "role": "CISA Coordinator",
          "options": [
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            {
              "automatable": "yes"
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          "version": "2.0.3",
          "timestamp": "2026-07-06T19:03:07.590667Z"
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          "product": "Gitea Open Source Git Server",
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  "published": "2026-07-03T21:16:56.660",
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      "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"
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  "lastModified": "2026-07-07T18:16:35.380",
  "sourceIdentifier": "88ee5874-cf24-4952-aea0-31affedb7ff2"
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