CVE-2026-82209
Estado: ModificadaAlta (8.2)—
When libpsl support is enabled, libcurl fails to enforce the Public Suffix List boundary check when processing a `Set-Cookie` header where the `Domain` attribute explicitly matches an origin host that is itself a public suffix (e.g., `Domain=co.uk` set by `co.uk`).
Instead of coercing it into a strict host-only cookie, libcurl saves the cookie with wildcard domain scope (`.co.uk`). Consequently, the cookie is inappropriately included in subsequent outbound requests or HTTP redirects to arbitrary sibling subdomains under the same public suffix (e.g., `attacker.co.uk`).
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: 0.37%
- Percentil entre todas las CVEs puntuadas: 29
- 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
T1539Steal Web Session Cookiecredential access65 % - Impacto secundario
T1598Phishing for Informationreconnaissance60 %
Vulnerabilidad remota sin autenticación (AV:N, PR:N, UI:N) en aplicación expuesta (libcurl). El impacto es fuga de cookies hacia dominios no autorizados bajo el mismo sufijo público, permitiendo robo de sesiones.
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-201
- CWE-201
Referencias
JSON original (NVD)
Mostrar
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"value": "When libpsl support is enabled, libcurl fails to enforce the Public Suffix\nList boundary check when processing a `Set-Cookie` header where the `Domain`\nattribute explicitly matches an origin host that is itself a public suffix\n(e.g., `Domain=co.uk` set by `co.uk`).\n\nInstead of coercing it into a strict host-only cookie, libcurl saves the\ncookie with wildcard domain scope (`.co.uk`). Consequently, the cookie is\ninappropriately included in subsequent outbound requests or HTTP redirects to\narbitrary sibling subdomains under the same public suffix (e.g.,\n`attacker.co.uk`)."
}
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