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.
Affected products
roundcube: webmail
References7
- roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1… Vendor Advisory
- github.com/roundcube/roundcubemail/commit/099009b9c8e1d3c636fb9… Patch
- github.com/roundcube/roundcubemail/commit/226811a1c974271dbedca… Patch
- github.com/roundcube/roundcubemail/commit/57dec0c127b98e0c8e3b9… Patch
- github.com/roundcube/roundcubemail/releases/tag/1.5.14 Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.6.14 Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.7-rc5 Release Notes
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 32 · as of 12 November 2026
- CWE
- CWE-669
Could this be exploited in your environment?
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