CVE-2019-11356 Explained : Impact and Mitigation

Cyrus IMAP versions 2.5.x through 2.5.12 and 3.0.x through 3.0.9 are vulnerable to a remote code execution flaw in the CalDAV functionality.

Understanding CVE-2019-11356

This CVE identifies a critical vulnerability in the CalDAV feature of Cyrus IMAP, allowing attackers to execute arbitrary code remotely.

What is CVE-2019-11356?

The vulnerability in the httpd component of Cyrus IMAP versions 2.5.x through 2.5.12 and 3.0.x through 3.0.9 enables attackers to execute malicious code remotely. This can be achieved by exploiting a flaw in processing specially crafted HTTP PUT requests for events with lengthy iCalendar property names.

The Impact of CVE-2019-11356

The exploitation of this vulnerability can lead to remote code execution, allowing attackers to take control of affected systems and potentially compromise sensitive data.

Technical Details of CVE-2019-11356

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The CalDAV functionality in Cyrus IMAP versions 2.5.x through 2.5.12 and 3.0.x through 3.0.9 contains a flaw that permits remote code execution via crafted HTTP PUT requests for events with lengthy iCalendar property names.

Affected Systems and Versions

Cyrus IMAP 2.5.x through 2.5.12
Cyrus IMAP 3.0.x through 3.0.9

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted HTTP PUT requests for events containing excessively long iCalendar property names, triggering the remote code execution.

Mitigation and Prevention

Protecting systems from CVE-2019-11356 requires immediate actions and long-term security measures.

Immediate Steps to Take

Apply security patches provided by Cyrus IMAP promptly.
Monitor network traffic for any suspicious activity related to HTTP PUT requests.
Implement network segmentation to limit the impact of potential attacks.

Long-Term Security Practices

Regularly update and patch all software components to address known vulnerabilities.
Conduct security assessments and penetration testing to identify and mitigate potential weaknesses.
Educate users and administrators about safe practices to prevent exploitation of vulnerabilities.

Patching and Updates

Refer to the official Cyrus IMAP release notes for versions 2.5.x, 3.0.x, 2.5.13, and 3.0.10 for detailed information on security updates.