CVE-2021-43413 : Security Advisory and Response
Learn about the CVE-2021-43413 affecting GNU Hurd, allowing unauthorized access and file modifications. Find mitigation steps and patching details here.
An issue was discovered in GNU Hurd before 0.9 20210404-9. A single pager port is shared among everyone who mmaps a file, allowing anyone to modify any files that they can read. This can be trivially exploited to get full root access.
Understanding CVE-2021-43413
This CVE involves a security vulnerability in GNU Hurd that could lead to unauthorized modification of files and potential root access.
What is CVE-2021-43413?
The vulnerability in GNU Hurd allows any user to modify files they can read due to the shared pager port, enabling unauthorized access.
The Impact of CVE-2021-43413
The vulnerability can be exploited to gain full root access, compromising the security and integrity of the system.
Technical Details of CVE-2021-43413
This section provides specific technical details about the CVE.
Vulnerability Description
The issue in GNU Hurd before 0.9 20210404-9 stems from the shared pager port, which permits file modification by any user who can read them.
Affected Systems and Versions
- Affected Version: GNU Hurd before 0.9 20210404-9
- All systems running the vulnerable GNU Hurd version
Exploitation Mechanism
- Users with read access to files can exploit the shared pager port to modify them.
Mitigation and Prevention
Protecting systems from CVE-2021-43413 requires immediate actions and long-term security practices.
Immediate Steps to Take
- Apply patches provided by GNU Hurd promptly
- Monitor system logs for unauthorized access
- Restrict file permissions to prevent unauthorized modifications
Long-Term Security Practices
- Regularly update software and apply security patches
- Implement access control mechanisms to limit file modification permissions
Patching and Updates
- Update GNU Hurd to version 0.9 20210404-9 or newer to address the vulnerability