CVE-2019-19726 Explained : Impact and Mitigation
Learn about CVE-2019-19726, a vulnerability in OpenBSD up to version 6.6 allowing local users to escalate privileges to root. Find out the impact, affected systems, exploitation mechanism, and mitigation steps.
CVE-2019-19726 is a vulnerability in OpenBSD up to version 6.6 that allows local users to escalate their privileges to root by exploiting a weakness in the checking mechanism for LD_LIBRARY_PATH in setuid programs.
Understanding CVE-2019-19726
This vulnerability enables attackers to execute their own library code as root by bypassing the security checks in certain setuid root programs.
What is CVE-2019-19726?
The security flaw in OpenBSD up to version 6.6 allows local users to elevate their privileges to root by manipulating the LD_LIBRARY_PATH environment variable in setuid programs.
The Impact of CVE-2019-19726
The vulnerability grants unauthorized users the ability to execute arbitrary code with elevated privileges, posing a significant security risk to affected systems.
Technical Details of CVE-2019-19726
This section provides detailed technical information about the vulnerability.
Vulnerability Description
The weakness in the checking mechanism for LD_LIBRARY_PATH in setuid programs, specifically chpass or passwd, allows attackers to execute their own library code as root.
Affected Systems and Versions
- Vendor: n/a
- Product: n/a
- Versions Affected: All versions up to OpenBSD 6.6
Exploitation Mechanism
By setting an extremely low RLIMIT_DATA resource limit, attackers can bypass the security check and gain root privileges when running setuid root programs.
Mitigation and Prevention
Protecting systems from CVE-2019-19726 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply patches and updates provided by OpenBSD to address the vulnerability.
- Monitor system logs for any suspicious activities related to privilege escalation.
Long-Term Security Practices
- Implement the principle of least privilege to restrict user access and permissions.
- Regularly audit and review setuid programs for potential security vulnerabilities.
Patching and Updates
- Stay informed about security advisories and updates from OpenBSD to promptly apply patches that mitigate the vulnerability.