RoundCube Webmail Cross-Site Scripting Vulnerability
RoundCube Webmail contains a cross-site scripting vulnerability. This vulnerability could allow a remote attacker to steal and send emails of a victim via a crafted e-mail message that abuses a Desanitization issue in message_body() in program/actions/mail/show.php.
A remote attacker, without authentication, can achieve full data confidentiality loss, arbitrary modification of data. Federal agencies are required to remediate by 2025-06-30 under CISA BOD 22-01.
This is a Cross-Site Scripting (XSS) (CWE-79) vulnerability in Roundcube Webmail. A Cross-Site Scripting vulnerability in Roundcube through 1.5.7 and 1.6.x through 1.6.7 allows a remote attacker to steal and send emails of a victim via a crafted e-mail message that abuses a Desanitization issue in message_body() in program/actions/mail/show.php. Exploitation requires remote network access, low attack complexity, no authentication required, and user interaction required.
📧
Phishing link
🖼
Malicious file
🔓
Server compromised
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: https://sonarsource.com/blog/government-emails-at-risk-critical-cross-site-scripting-vulnerability-in-roundcube-webmail/
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
References
No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.
References