PT-2026-29979 · Roundcube · Webmail

Published 2026-04-03 · Updated 2026-04-03 · CVE-2026-35540

Mitre

CVSS v3.1

5.4

Medium

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

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.

Fix

Weakness Enumeration

CWE-669

Related Identifiers

CVE-2026-35540

Affected Products

Webmail

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2026-35540 · Security Note
• https://github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942 · Note
• https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5 · Note
• https://github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870 · 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