CVE-2018-20749 : Exploit Details and Defense Strategies
Learn about CVE-2018-20749, a vulnerability in LibVNC before version 0.9.12 allowing a heap out-of-bounds write. Find out the impact, affected systems, exploitation details, and mitigation steps.
LibVNC before version 0.9.12 has a vulnerability in libvncserver/rfbserver.c that allows a heap out-of-bounds write. The previous fix for CVE-2018-15127 was not fully effective.
Understanding CVE-2018-20749
This CVE involves a heap out-of-bounds write vulnerability in LibVNC's rfbserver.c file.
What is CVE-2018-20749?
LibVNC version prior to 0.9.12 is susceptible to a heap out-of-bounds write issue in the rfbserver.c file, with an incomplete fix for a previous CVE-2018-15127.
The Impact of CVE-2018-20749
The vulnerability could allow an attacker to execute arbitrary code or cause a denial of service by triggering a heap out-of-bounds write.
Technical Details of CVE-2018-20749
This section covers specific technical aspects of the CVE.
Vulnerability Description
The vulnerability in LibVNC's rfbserver.c file allows for a heap out-of-bounds write, potentially leading to code execution or denial of service.
Affected Systems and Versions
- Product: Not applicable
- Vendor: Not applicable
- Versions: All versions prior to 0.9.12
Exploitation Mechanism
Attackers can exploit this vulnerability by sending specially crafted requests to the affected server, triggering the out-of-bounds write.
Mitigation and Prevention
Protecting systems from CVE-2018-20749 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply the latest security updates provided by LibVNC to address the vulnerability.
- Monitor network traffic for any signs of exploitation attempts.
- Consider implementing network segmentation to limit the impact of potential attacks.
Long-Term Security Practices
- Regularly update software and systems to patch known vulnerabilities.
- Conduct security assessments and penetration testing to identify and address weaknesses.
- Educate users and administrators about safe computing practices to prevent exploitation.
Patching and Updates
Ensure that all instances of LibVNC are updated to version 0.9.12 or newer to mitigate the vulnerability.