CVE-2017-5669 : Exploit Details and Defense Strategies
Learn about CVE-2017-5669, a vulnerability in the Linux kernel allowing local users to bypass protection mechanisms. Find mitigation steps and long-term security practices here.
In the Linux kernel up to version 4.9.12, a vulnerability exists in the do_shmat function in ipc/shm.c. This flaw allows local users to map page zero and bypass protection mechanisms for the mmap system call.
Understanding CVE-2017-5669
This CVE entry highlights a vulnerability in the Linux kernel that could be exploited by local users to evade security mechanisms.
What is CVE-2017-5669?
The do_shmat function in ipc/shm.c in the Linux kernel through version 4.9.12 does not restrict the address calculated by a certain rounding operation. This oversight enables local users to map page zero and bypass a protection mechanism for the mmap system call by executing crafted shmget and shmat system calls in a privileged context.
The Impact of CVE-2017-5669
The vulnerability allows local users to manipulate memory mappings and potentially escalate privileges, posing a risk to the integrity and security of affected systems.
Technical Details of CVE-2017-5669
This section delves into the technical aspects of the CVE entry.
Vulnerability Description
The do_shmat function in ipc/shm.c in the Linux kernel through 4.9.12 allows local users to map page zero, bypassing protection mechanisms for the mmap system call.
Affected Systems and Versions
- Linux kernel versions up to 4.9.12
Exploitation Mechanism
To exploit this vulnerability, an attacker must execute carefully crafted shmget and shmat system calls within a privileged context.
Mitigation and Prevention
Understanding how to mitigate and prevent the exploitation of this vulnerability is crucial.
Immediate Steps to Take
- Apply patches provided by the Linux kernel maintainers promptly.
- Monitor security advisories for updates and follow best practices for system security.
Long-Term Security Practices
- Implement the principle of least privilege to restrict user access and actions.
- Regularly update and patch the Linux kernel to address security vulnerabilities.
Patching and Updates
- Stay informed about security updates and patches released by the Linux kernel community.