PT-2026-29978 · Roundcube · Webmail

Published 2026-04-03 · Updated 2026-04-03 · CVE-2026-35539

NVD

CVSS v3.1

6.1

Medium

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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.

Fix

XSS

Weakness Enumeration

CWE-79

Related Identifiers

CVE-2026-35539

Affected Products

Webmail

References · 8

• https://nvd.nist.gov/vuln/detail/CVE-2026-35539 · Security Note
• https://github.com/roundcube/roundcubemail/commit/1b30edf5369668c92fe91dae3d52e477c808aa4f · Note
• https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5 · Note
• https://github.com/roundcube/roundcubemail/releases/tag/1.5.14 · Note
• https://github.com/roundcube/roundcubemail/commit/d742954ccbcdee7020f8f2e7c49ce0fca5a0efab · Note
• https://github.com/roundcube/roundcubemail/commit/10a6d1fa8acac85c727b0a6ae4a6642bfa27bea1 · Note
• https://github.com/roundcube/roundcubemail/releases/tag/1.6.14 · Note
• https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14 · Note