CVE-2023-43770: Roundcube Webmail Persistent Cross-Site Scripting (XSS) Vulnerability

Medium severity, CVSS 6.1. Actively exploited: in CISA KEV since 2024-02-12. EPSS: 63.7% chance of exploitation in the next 30 days.

Roundcube before 1.4.14, 1.5.x before 1.5.4, and 1.6.x before 1.6.3 allows XSS via text/plain e-mail messages with crafted links because of program/lib/Roundcube/rcube_string_replacer.php behavior.

Affected products

• Debian Debian Linux: version 10.0 only
• Roundcube Webmail: before 1.4.14 (fixed in 1.4.14); from 1.5.0, before 1.5.4 (fixed in 1.5.4); from 1.6.0, before 1.6.3 (fixed in 1.6.3)

Published 2023-09-22. Last modified 2026-06-17.