Description
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, 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. This issue exists because of insufficient fixes for CVE-2026-35540, CVE-2026-48843 and CVE-2026-62643.
Affected products
roundcube: webmail
References7
- roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3 Vendor Advisory
- github.com/roundcube/roundcubemail/commit/7e10ca0110b7c9aa1b785… Patch
- github.com/roundcube/roundcubemail/commit/8a92380b06b5df1481e03… Patch
- github.com/roundcube/roundcubemail/commit/92f85c883594e5be75715… Patch
- github.com/roundcube/roundcubemail/commit/c111b72950cd2bf57d6b8… Patch
- github.com/roundcube/roundcubemail/releases/tag/1.6.18 Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.7.3 Release Notes
Metrics
- CVSS 3.1
-
5.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 36 · as of 11 November 2026
- CWE
- CWE-918
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