CVE-2019-5603 : Security Advisory and Response
Learn about CVE-2019-5603, a FreeBSD vulnerability allowing unauthorized access to files and directories. Find mitigation steps and system protection strategies here.
A vulnerability in FreeBSD versions prior to specific releases could allow a malicious user to gain unauthorized access to files and directories.
Understanding CVE-2019-5603
This CVE involves a flaw in FreeBSD that could lead to a counter overflow, potentially enabling unauthorized access to system resources.
What is CVE-2019-5603?
The vulnerability in FreeBSD versions prior to certain releases could allow a malicious user to exploit system calls involving file descriptors within mqueuefs, leading to a counter overflow.
The Impact of CVE-2019-5603
The vulnerability could permit a malicious user to access files, directories, and sockets opened by processes owned by other users, compromising system security.
Technical Details of CVE-2019-5603
This section provides detailed technical information about the CVE-2019-5603 vulnerability.
Vulnerability Description
In FreeBSD versions before specific releases, system calls operating on file descriptors within mqueuefs did not properly release the reference, potentially allowing a malicious user to overflow the counter and gain unauthorized access to system resources.
Affected Systems and Versions
- FreeBSD versions 12.0-STABLE prior to r350261
- FreeBSD 12.0-RELEASE prior to 12.0-RELEASE-p8
- FreeBSD 11.3-STABLE prior to r350263
- FreeBSD 11.3-RELEASE prior to 11.3-RELEASE-p1
- FreeBSD 11.2-RELEASE prior to 11.2-RELEASE-p12
Exploitation Mechanism
The vulnerability arises during system calls involving file descriptors within mqueuefs, where the reference release is not performed correctly, leading to a counter overflow that could be exploited by a malicious user.
Mitigation and Prevention
Protect your systems from CVE-2019-5603 with these mitigation strategies.
Immediate Steps to Take
- Apply the necessary patches provided by FreeBSD to address the vulnerability.
- Monitor system logs for any suspicious activities that may indicate exploitation of the vulnerability.
Long-Term Security Practices
- Regularly update FreeBSD to the latest stable releases to ensure all security patches are applied.
- Implement the principle of least privilege to restrict user access and minimize the impact of potential security breaches.
Patching and Updates
- Stay informed about security advisories from FreeBSD and promptly apply any patches or updates released to address vulnerabilities.