CVE-2026-55761
Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. In versions 2.39.0 through 2.39.3 and 2.40.0 until 2.43.0, unauthenticated restore and administrator initialization endpoints (/api/restore and /api/users/admin/init) remain accessible during the five-minute setup window for uninitialized instances, allowing a network attacker to restore a crafted backup or create the first administrator account and gain full administrative access. This issue is fixed in versions 2.39.4 and 2.43.0.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 7.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.49%
- Percentil entre todas las CVEs puntuadas: 40
- Fecha de la puntuación: 5/10/2026
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.
- Explotación
T1190Exploit Public-Facing Applicationinitial access90 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access95 % - Impacto secundario
T1556Modify Authentication Processdefense impairment · persistence · credential access85 %
Aplicación web expuesta (AV:N, PR:N) permite crear cuenta admin sin autenticación en ventana de setup, otorgando acceso administrativo completo y control de autenticación (CWE-287).
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
Tecnologías afectadas (1)
CWE
- CWE-287
- NVD-CWE-noinfo
Referencias
- https://github.com/portainer/portainer/commit/49f19107cf9a3540cbe406c9eb7f24390e1af02b
- https://github.com/portainer/portainer/commit/d2b56efcb4e43c4168bb6688eee9f6bf22867312
- https://github.com/portainer/portainer/issues/2770
- https://github.com/portainer/portainer/releases/tag/2.39.4
- https://github.com/portainer/portainer/releases/tag/2.43.0
- https://github.com/portainer/portainer/security/advisories/GHSA-x626-fcwx-f5pc
JSON original (NVD)
Mostrar
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