CVE-2026-35539
Roundcube Webmail: Insufficient HTML attachment sanitization in preview mode
6.1
MEDIUM
CVSS 3.1
EPSS 0.01%
Description
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.
How to fix CVE-2026-35539
To remediate CVE-2026-35539, upgrade the affected package to a fixed version below.
- Debian/roundcube—upgrade to 1.4.15+dfsg.1-1+deb11u8 or later
- —upgrade to 1.7-rc5 or later
Is CVE-2026-35539 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 1.4.15+dfsg.1-1+deb11u8
- >= 1.7-beta, < 1.7-rc5
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |