CVE-2026-114717 Roundcube CVE debrief

Who should care

Defenders responsible for Roundcube Webmail installations, particularly those using versions before 1.6.20 and 1.7.5, should assess exposure and apply patches. This includes operators managing Roundcube Webmail, platform administrators, vulnerability management teams, and security teams responsible for mail server security. They should verify versions, review inventory, and monitor for suspicious activity related to mail header injection attacks.

Why it matters

CVE-2026-114717 is a medium-severity vulnerability in Roundcube Webmail that allows for mail header injection attacks. Defenders should prioritize verifying exposure and applying patches for affected versions.

• Potential for mail header injection attacks
• Need for verification of Roundcube Webmail versions and patch application
• Possible impact on mail server security

Technical summary

The vulnerability occurs when a message is forwarded as an attachment in Roundcube Webmail. The subject of the forwarded message is used to generate the attachment name without proper sanitization, allowing for CRLF sequences to inject arbitrary MIME part headers. This medium-severity vulnerability affects Roundcube Webmail versions before 1.6.20 and 1.7.5. The issue was fixed in commits that collapse whitespace in the generated name, preventing header injection attacks. Defenders should prioritize verifying exposure and applying patches for affected versions.

Defensive priority

Defenders should prioritize verifying exposure and applying patches for Roundcube Webmail versions before 1.6.20 and 1.7.5.

Recommended defensive actions

• Verify Roundcube Webmail version and apply patches for versions before 1.6.20 and 1.7.5
• Review and update inventory of Roundcube Webmail installations
• Monitor for suspicious activity related to mail header injection
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record and source item provide details on the vulnerability, affected versions, and patches. However, there is limited information on exploitation or victim impact. Defenders should verify Roundcube Webmail versions, assess exposure, and apply patches. Evidence from the CVE Program and NVD detail pages indicates a medium-severity vulnerability. Limited source information suggests verifying installation versions and applying patches as key defensive actions.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.