Description


Missing Host header validation and missing throttling of failed administrator sign-ins in the REST API listener of Progressive Robot hMailServer 6.0.0 through 6.3.5 allow a remote attacker to brute-force the server administrator's password through the administrator's own browser by DNS rebinding. The listener, which is off by default and bound to the loopback when enabled, answered requests whatever their Host header named, and a failed sign-in with the administrator's password from the loopback was neither auto-banned nor delayed. A web page whose host name the attacker rebinds to 127.0.0.1, opened in a browser on the server, can therefore send authenticated requests to the listener, read the answers and try administrator passwords at full speed until one is accepted, giving the attacker full administrative control of the mail server.

Related CPE's


Could not find any relations

Weaknesses



CWE-346

CVSS impact metrics


CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

7.5 · High

Information


Source identifier

[email protected]

Vulnerability status

Deferred

Published

2026-10-08T11:16:44.013Z

21 hours ago

Last modified

2026-10-08T21:02:43.860Z

12 hours ago