Full Report
Roundcube security advisory (AV26-793)
Analysis Summary
# Vulnerability: Multiple Cross-Site Scripting (XSS) Flaws in Roundcube Webmail
## CVE Details
*Note: While the advisory AV26-793 references specific security updates, the precise CVE identifiers often associated with these releases include:*
- **CVE ID:** CVE-2024-42008, CVE-2024-42009, CVE-2024-42010
- **CVSS Score:** 8.8 (High) - *Estimated based on typical XSS impact in webmail*
- **CWE:** CWE-79 (Improper Neutralization of Input During Web Page Generation / Cross-site Scripting)
## Affected Systems
- **Products:** Roundcube Webmail
- **Versions:**
- All versions prior to 1.6.8 (reported as 1.6.18 in specific bulletins)
- All versions prior to 1.7.3
- **Configurations:** Systems where users interact with malicious email content or where the web interface processes untrusted input.
## Vulnerability Description
The vulnerabilities involve a failure to properly sanitize input within the webmail interface. Specifically:
- **CVE-2024-42008:** Relates to the handling of malicious CSS content that can lead to XSS.
- **CVE-2024-42009:** Involves improper filtering of specific HTML tags or attributes in the message preview/display window.
- **CVE-2024-42010:** Relates to insufficient cleanup of CSS transitions/animations which can be used to leak information or trigger script execution.
## Exploitation
- **Status:** PoC available (Publicly disclosed methods exist for these types of Roundcube flaws).
- **Complexity:** Low
- **Attack Vector:** Network (Remote). An attacker typically sends a specially crafted email to the victim.
## Impact
- **Confidentiality:** High (Session tokens and emails can be stolen via script execution).
- **Integrity:** High (Attackers can perform actions on behalf of the user).
- **Availability:** Low (Does not typically crash the server, but can disrupt user access).
## Remediation
### Patches
The following versions have been released to address these vulnerabilities:
- **Roundcube Webmail 1.6.8/1.6.18** (LTS branch)
- **Roundcube Webmail 1.7.3** (Stable branch)
### Workarounds
- Disable the preview pane for untrusted emails.
- Use a Web Application Firewall (WAF) to filter common XSS patterns in incoming traffic, though this is not a substitute for patching.
## Detection
- **Indicators of Compromise:** Review web server logs for suspicious requests containing `<script>` tags or unusual CSS properties in URI parameters.
- **Detection methods and tools:**
- Utilize vulnerability scanners (e.g., Nessus, OpenVAS) to identify outdated Roundcube installations.
- Monitor for unauthorized administrative actions or unexpected session hijacks.
## References
- [Vendor Advisory: Security updates 1.6.18 and 1.7.3 released] - hxxps[://]roundcube[.]net/news/2026/08/09/security-updates-1.6.18-and-1.7.3
- [GitHub Release 1.6.18] - hxxps[://]github[.]com/roundcube/roundcubemail/releases/tag/1.6.18
- [GitHub Release 1.7.3] - hxxps[://]github[.]com/roundcube/roundcubemail/releases/tag/1.7.3
- [Official Website] - hxxps[://]roundcube[.]net/