Improper Neutralization of Special Elements in Output Used by a Downstream Component in Roundcube Webmail - #VU147182
Published: September 6, 2026
Vulnerability identifier: #VU147182
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-74
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to smuggle CSS declarations.
The vulnerability exists due to improper neutralization of special elements in CSS declaration handling when emitting unencoded ampersands. A remote attacker can supply crafted CSS content to smuggle CSS declarations.
Affected software
Roundcube Webmail
Remediation
Install security update from vendor's website.
Roundcube Webmail - addressed in versions 1.6.19, 1.7.4