Protection mechanism failure in Roundcube Webmail - #VU162688
Published: November 9, 2026
Vulnerability identifier: #VU162688
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-693
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass configured trusted-host restrictions during URL resolution.
The vulnerability exists due to failure to enforce the trusted host setting in Roundcube Webmail's resolve_url() function when resolving URLs. A remote attacker can supply untrusted host information to influence URL resolution outside the configured trust restrictions.
Affected software
Roundcube Webmail
Remediation
Install security update from vendor's website.
Roundcube Webmail - addressed in versions 1.6.21, 1.7.6