CVE-2026-35544

MEDIUM

Roundcube Webmail <1.5.14 - CSS Sanitization Bypass

Title source: llm

Description

An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.

References (7)

https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14

https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5

https://github.com/roundcube/roundcubemail/commit/226811a1c974271dbedca72672923abaff8191c0

https://github.com/roundcube/roundcubemail/releases/tag/1.6.14

https://github.com/roundcube/roundcubemail/commit/099009b9c8e1d3c636fb9a5af72f7c2596018662

https://github.com/roundcube/roundcubemail/releases/tag/1.5.14

https://github.com/roundcube/roundcubemail/commit/57dec0c127b98e0c8e3b9c26c80049b9c4bcaea7

View Patch ZIP pw:eip

Scores

CVSS v3 5.3

EPSS 0.0004

EPSS Percentile 13.0%

Attack Vector NETWORK

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

CISA SSVC

Vulnrichment

Exploitation none

Automatable yes

Technical Impact partial

Details

CWE

CWE-669

Status published

Products (4)

roundcube/roundcubemail 1.7-beta - 1.7-rc5Packagist

roundcube/webmail < 1.5.13

Roundcube/Webmail < 1.5.14

Roundcube/Webmail 1.6.0 - 1.6.14

Published Apr 03, 2026

Tracked Since Apr 03, 2026