CVE-2026-35539: Roundcube Webmail: Insufficient HTML attachment sanitization in preview mode
(updated )
An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. XSS exists because of insufficient HTML attachment sanitization in preview mode. A victim must preview a text/html attachment.
References
- github.com/advisories/GHSA-x4q5-8j5g-hpjc
- github.com/roundcube/roundcubemail
- github.com/roundcube/roundcubemail/commit/10a6d1fa8acac85c727b0a6ae4a6642bfa27bea1
- github.com/roundcube/roundcubemail/commit/1b30edf5369668c92fe91dae3d52e477c808aa4f
- github.com/roundcube/roundcubemail/commit/d742954ccbcdee7020f8f2e7c49ce0fca5a0efab
- github.com/roundcube/roundcubemail/releases/tag/1.5.14
- github.com/roundcube/roundcubemail/releases/tag/1.6.14
- github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
- nvd.nist.gov/vuln/detail/CVE-2026-35539
- roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14
Code Behaviors & Features
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