CVE-2026-35540: Roundcube Webmail: Insufficient CSS sanitization in HTML e-mail messages
(updated )
An issue was discovered in Roundcube Webmail 1.6.0 before 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to SSRF or Information Disclosure, e.g., if stylesheet links point to local network hosts.
References
- github.com/advisories/GHSA-vxg2-hhgr-37fx
- github.com/roundcube/roundcubemail
- github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870
- github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942
- github.com/roundcube/roundcubemail/releases/tag/1.6.14
- github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
- nvd.nist.gov/vuln/detail/CVE-2026-35540
- roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14
Code Behaviors & Features
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