CVE-2017-5581 Explained : Impact and Mitigation

TigerVNC versions prior to 1.7.1 are affected by a buffer overflow vulnerability in the ModifiablePixelBuffer::fillRect function. Remote servers can exploit this vulnerability to execute unauthorized code by sending a specific message.

Understanding CVE-2017-5581

What is CVE-2017-5581?

The vulnerability in TigerVNC versions before 1.7.1 allows remote servers to execute unauthorized code by exploiting a buffer overflow in the ModifiablePixelBuffer::fillRect function.

The Impact of CVE-2017-5581

This vulnerability poses a significant risk as it enables remote attackers to execute arbitrary code on the affected system, potentially leading to unauthorized access and control.

Technical Details of CVE-2017-5581

Vulnerability Description

The buffer overflow in the ModifiablePixelBuffer::fillRect function in TigerVNC versions prior to 1.7.1 allows remote servers to execute arbitrary code by sending a specific message with a subrectangle outside the framebuffer boundaries.

Affected Systems and Versions

Product: TigerVNC
Vendor: TigerVNC
Versions affected: All versions prior to 1.7.1

Exploitation Mechanism

Remote servers can exploit this vulnerability by sending an RRE message with a subrectangle that exceeds the boundaries of the framebuffer.

Mitigation and Prevention

Immediate Steps to Take

Update TigerVNC to version 1.7.1 or later to mitigate the vulnerability.
Monitor network traffic for any suspicious activity that could indicate exploitation attempts.

Long-Term Security Practices

Regularly update software and apply security patches to prevent known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

Ensure that all systems running TigerVNC are regularly updated with the latest security patches and versions to address known vulnerabilities.