CVE-2020-5214 : Exploit Details and Defense Strategies

NetHack error recovery after syntax error in configuration file is subject to a buffer overflow.

Understanding CVE-2020-5214

What is CVE-2020-5214?

In NetHack before 3.6.5, a vulnerability exists where detecting an unknown configuration file option can lead to a buffer overflow, resulting in a crash or potential remote code execution/privilege escalation.

The Impact of CVE-2020-5214

This vulnerability affects systems with NetHack installed suid/sgid and shared systems allowing users to upload their configuration files. Upgrading to NetHack 3.6.5 is recommended.

Technical Details of CVE-2020-5214

Vulnerability Description

The vulnerability in NetHack before 3.6.5 allows a buffer overflow due to detecting unknown configuration file options, potentially leading to a crash or remote code execution/privilege escalation.

Affected Systems and Versions

Product: NetHack
Vendor: NetHack
Versions Affected: < 3.6.5

Exploitation Mechanism

The vulnerability can be exploited on systems with NetHack installed suid/sgid and shared systems that permit users to upload their configuration files.

Mitigation and Prevention

Immediate Steps to Take

Upgrade to NetHack version 3.6.5 to mitigate the vulnerability.
Avoid running NetHack with elevated privileges.
Restrict user permissions on shared systems.

Long-Term Security Practices

Regularly update software to the latest versions.
Implement principle of least privilege to limit potential impact of vulnerabilities.
Conduct security assessments and audits to identify and address vulnerabilities.

Patching and Updates

Ensure timely installation of security patches and updates to protect against known vulnerabilities.