CVE-2026-75002 Roundcube CVE debrief

Who should care

Organizations and users of Roundcube Webmail, especially those using versions before 1.6.18 and 1.7.3, should be aware of this vulnerability and take necessary actions to mitigate the risk. This includes IT administrators, security teams, and individuals responsible for maintaining and securing email services within their organizations. Prompt action is crucial to prevent potential information disclosure or privilege escalation via IMAP command injection, which could have significant security implications if left unaddressed. Affected parties should review and apply patches or updates as recommended by the vendor to ensure the security and integrity of their email services. Additionally, monitoring for suspicious activity and implementing compensating controls may be necessary until patches can be applied. Effective communication and coordination among stakeholders are essential to ensure a timely and effective response to this vulnerability. By taking proactive measures, organizations can minimize the risk associated with CVE-2026-75002 and protect their email services from potential exploitation. This vulnerability underscores the importance of maintaining up-to-date software and vigilant security practices to safeguard against emerging threats. Therefore, it is imperative that organizations take immediate action to address this vulnerability and prevent potential security breaches. The consequences of inaction could be severe, ranging from unauthorized access to sensitive information to significant disruptions in email services. By prioritizing the patching of vulnerable systems and implementing appropriate security measures, organizations can effectively mitigate the risks associated with CVE-2026-75002 and maintain the security and reliability of their email services. In conclusion, the CVE-2026-75002 vulnerability in Roundcube Webmail poses a significant risk to organizations and users, and prompt action is necessary to prevent potential security breaches and ensure the integrity of email services. By taking proactive measures and prioritizing security, organizations can effectively address this vulnerability and protect their email services from potential

Technical summary

The CVE-2026-75002 vulnerability in Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3 allows for mail search and LITERAL+ byte-count desynchronization, potentially leading to information disclosure or privilege escalation via IMAP command injection. This vulnerability is a result of inadequate handling of IMAP commands, which can be exploited by attackers to gain unauthorized access or manipulate email content. Organizations using Roundcube Webmail should prioritize patching to prevent potential information disclosure or privilege escalation via IMAP command injection.

Defensive priority

Organizations using Roundcube Webmail should prioritize patching to prevent potential information disclosure or privilege escalation via IMAP command injection.

Recommended defensive actions

• Apply patches for Roundcube Webmail versions 1.6.18 and 1.7.3
• Restrict IMAP command injection
• Monitor for suspicious activity
• 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.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE-2026-75002 record indicates that mail search and LITERAL+ byte-count desynchronization in Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3 could lead to information disclosure or privilege escalation via IMAP command injection. However, detailed information about the vulnerability is limited in the provided source corpus.

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.