Vulnerabilidad · Publicado 08/10/2026
Se ha identificado una vulnerabilidad de cross-site scripting (XSS) en el cliente webmail de Progressive Robot hMailServer que afecta versiones 6.3.2 a 6.3.5. Un atacante remoto puede enviar mensajes cifrados (S/MIME u OpenPGP) que, al ser descifrados en el navegador, ejecutan código malicioso con los permisos de sesión del usuario. Esto compromete la confidencialidad de correos y credenciales en empresas que usan este servidor de correo.
Cross-site scripting in the webmail of Progressive Robot hMailServer 6.3.2 through 6.3.5 allows a remote attacker who can send a user an encrypted message to run script in the webmail's origin with that user's session. When the webmail decrypted an S/MIME message (from 6.3.2) or an OpenPGP message (from 6.3.4) in the browser, it offered each decrypted attachment as a blob URL of the media type the message declared for it. A click saved the file, but if the user opened the attachment in a new tab, a part declared as text/html was rendered as a document of the webmail's origin and its script could read the mailbox, send mail and change the account through the REST API. The webmail is served only when the REST API is enabled, which it is not by default.
Score: 8/10 — Severidad: HIGH — Estado NIST: Received
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
CWE-79
Publicado en NIST NVD.