CVE-2026-34531
Flask-HTTPAuth provides Basic, Digest and Token HTTP authentication for Flask routes. Prior to version 4.8.1, in a situation where the client makes a request to a token protected resource without passing a token, or passing an empty token, Flask-HTTPAuth would invoke the application's token verification callback function with the token argument set to an empty string. If the application had any users in its database with an empty string set as their token, then it could potentially authenticate the client request against any of those users. This issue has been patched in version 4.8.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N
- Puntuación base: 8.2
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: 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 access85 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access90 %
Vulnerabilidad en autenticación remota (AV:N, PR:N): bypass sin credenciales válidas pasando token vacío. CWE-287 (autenticación débil) permite acceso no autorizado a recursos protegidos.
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/miguelgrinberg/Flask-HTTPAuth/releases/tag/v4.8.1
- https://github.com/miguelgrinberg/Flask-HTTPAuth/security/advisories/GHSA-p44q-vqpr-4xmg
- https://github.com/miguelgrinberg/flask-httpauth/commit/b15ffe9e50e110d7174ccd944f642079e1dcf9ee
- https://lists.debian.org/debian-lts-announce/2026/05/msg00049.html
JSON original (NVD)
Mostrar
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