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CVE-2026-91973

Estado: AplazadaAlta (8.7)—

Vikunja before 2.6.0 contains an authentication bypass vulnerability in CalDAV BasicAuth endpoints that lack rate limiting protection. Remote unauthenticated attackers can issue unbounded credential-guessing requests against /dav, /.well-known, and /feeds routes to bypass the instance's anti-brute-force controls and compromise password-only accounts.

CVSS

Probabilidad de explotación (EPSS)

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.

Acceso remoto sin autenticación a endpoints CalDAV con falta de rate limiting (CWE-307) permite bypass de controles anti-fuerza bruta; AV:N, PR:N, UI:N confirman T1190. Impactos: compromiso de cuentas (T1078.001) mediante fuerza bruta desprotegida (T1110.001).

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

Password PoliciesMulti-factor AuthenticationUpdate SoftwareVulnerability ScanningPrivileged Account ManagementNetwork Segmentation

Tecnologías afectadas (1)

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

Vikunja — VikunjaAI

CWE

Referencias

JSON original (NVD)

Mostrar
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}