medium5.3
CVE-2026-35544
Roundcube Webmail: Insufficient CSS sanitization in HTML e-mail messages
Impact
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 packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | roundcube/roundcubemail | >= 1.7-beta, < 1.7-rc5 | 1.7-rc5 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Roundcube | Webmail | through 1.5.13 from 1.6.0 through 1.6.13 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-xpqh-grpw-4xmg
- https://nvd.nist.gov/vuln/detail/CVE-2026-35544
- https://github.com/roundcube/roundcubemail/commit/099009b9c8e1d3c636fb9a5af72f7c2596018662
- https://github.com/roundcube/roundcubemail/commit/226811a1c974271dbedca72672923abaff8191c0
- https://github.com/roundcube/roundcubemail/commit/57dec0c127b98e0c8e3b9c26c80049b9c4bcaea7
- https://github.com/roundcube/roundcubemail/releases/tag/1.5.14
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.14
- https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
- https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14