CVE-2026-114724 Roundcube CVE debrief

Who should care

Defenders responsible for Roundcube Webmail instances, particularly those using versions before 1.6.20 and 1.7.5, should assess exposure and apply patches. This includes IT administrators, security teams, and vulnerability management teams. They should also monitor for suspicious session activity and verify inventory of Roundcube Webmail instances.

Why it matters

CVE-2026-114724 is a high-severity vulnerability in Roundcube Webmail, allowing for object injection via manipulated session keys. Defenders should assess exposure and apply patches for versions before 1.6.20 and 1.7.5.

• Potential for object injection via manipulated session keys
• Requires verification of affected versions and exposure
• Defenders must assess and patch vulnerable instances
• Monitoring for suspicious session activity is necessary

Technical summary

CVE-2026-114724 is a high-severity vulnerability in Roundcube Webmail, allowing for object injection via a manipulated session key prefixed with '!'. This issue affects versions before 1.6.20 and 1.7.5. An attacker able to influence stored session data can exploit this vulnerability, potentially leading to unauthorized access or code execution. The vulnerability was publicly disclosed on October 22, 2026, and last modified on October 28, 2026. Defenders should assess exposure and apply patches for vulnerable instances.

Defensive priority

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

Recommended defensive actions

• Assess exposure of Roundcube Webmail instances to CVE-2026-114724
• Apply patches for versions before 1.6.20 and 1.7.5
• Monitor for suspicious session activity
• Verify inventory of Roundcube Webmail instances
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, while Roundcube's official advisory and Debian's issue tracking page offer additional context. The vulnerability has a CVSS score of 7.4 and is considered high-severity. There is no information on known exploit activity or ransomware campaign use. Defenders should verify affected versions, assess exposure, and apply patches.

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.