CVE-2026-91766
When the http:// stream wrapper follows a redirect it forwards the user-supplied Authorization, Cookie and Proxy-Authorization headers unchanged, even when the redirect target is a different host, a different port, or a downgrade from HTTPS to HTTP. A server that can steer a redirect therefore receives credentials that were only meant for the original origin. This is the same class of issue that libcurl fixed in 7.58.0 ( CVE-2018-1000007 https://github.com/advisories/GHSA-g7x2-hrfp-pv5f ).
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 5.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.34%
- Percentil entre todas las CVEs puntuadas: 25
- 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 access75 % - Impacto principal
T1552.007Container APIcredential access85 % - Impacto secundario
T1005Data from Local Systemcollection70 %
Explotación de la aplicación web PHP mediante seguimiento de redirecciones que expone credenciales (headers de autorización) a hosts no autorizados. CWE-200, CWE-522 confirman divulgación de información sensible.
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)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-200, CWE-522
Referencias
JSON original (NVD)
Mostrar
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"timestamp": "2026-09-28T12:56:20.823835Z"
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"published": "2026-09-25T21:17:24.673",
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"lastModified": "2026-09-29T21:27:41.130",
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