CVE-2026-35539 — Cross-site Scripting in Webmail

CWE-79 — Cross-site Scripting9 documents7 sources
Severity
6.1MEDIUMNVD
EPSS
0.0%
top 87.69%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Roundcube WebmailRoundcube Roundcubemail
Timeline
PublishedApr 3

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.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NExploitability: 2.8 | Impact: 2.7

Affected Packages3 packages

▶CVEListV5roundcube/webmail1.6.0 — 1.6.14+1
▶NVDroundcube/webmail1.6.0 — 1.6.14+1
▶Packagistroundcube/roundcubemail1.7-beta — 1.7-rc5

Patches

Patch: github.com ↗Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

4
OSV
Roundcube Webmail: Insufficient HTML attachment sanitization in preview mode↗2026-04-03
▶
OSV
CVE-2026-35539: An issue was discovered in Roundcube Webmail before 1↗2026-04-03
▶
GHSA
Roundcube Webmail: Insufficient HTML attachment sanitization in preview mode↗2026-04-03
▶
CVEList
CVE-2026-35539: An issue was discovered in Roundcube Webmail before 1↗2026-04-03
▶

📋Vendor Advisories

1
Debian
CVE-2026-35539: roundcube - An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. XSS exist...↗2026
▶

🕵️Threat Intelligence

1
Wiz
CVE-2026-35539 Impact, Exploitability, and Mitigation Steps | Wiz↗
▶

💬Community

2
Bugzilla
CVE-2026-35538 CVE-2026-35539 CVE-2026-35540 CVE-2026-35541 CVE-2026-35542 CVE-2026-35544 roundcubemail: various flaws [epel-all]↗2026-04-03
▶
Bugzilla
CVE-2026-35538 CVE-2026-35539 CVE-2026-35540 CVE-2026-35541 CVE-2026-35542 CVE-2026-35544 roundcubemail: various flaws [fedora-all]↗2026-04-03
▶
CVE-2026-35539 — Cross-site Scripting in Webmail | cvebase