CVE-2021-44733 : Security Advisory and Response
Learn about CVE-2021-44733, a use-after-free flaw in Linux kernel's TEE subsystem. Understand the impact, affected versions, and mitigation steps for this security vulnerability.
A use-after-free vulnerability was found in the TEE subsystem in the Linux kernel through version 5.15.11. This vulnerability is tracked as CVE-2021-44733.
Understanding CVE-2021-44733
The vulnerability identified as CVE-2021-44733 involves a use-after-free issue in the Linux kernel's TEE subsystem, which may lead to a security compromise.
What is CVE-2021-44733?
A race condition in the tee_shm_get_from_id function in drivers/tee/tee_shm.c in the Linux kernel can trigger a use-after-free scenario when attempting to free a shared memory object, potentially exploited by attackers.
The Impact of CVE-2021-44733
The exploitation of this vulnerability could allow an attacker to execute arbitrary code or escalate privileges on a targeted system through specially crafted operations.
Technical Details of CVE-2021-44733
This section delves into the specific technical aspects of CVE-2021-44733.
Vulnerability Description
The vulnerability is due to a race condition in the tee_shm_get_from_id function of the TEE subsystem in the Linux kernel, which can result in a use-after-free situation, posing a security risk.
Affected Systems and Versions
- Systems with the Linux kernel through version 5.15.11
- Specific configurations utilizing the TEE subsystem may be vulnerable
Exploitation Mechanism
Attackers can potentially trigger the use-after-free condition by manipulating the tee_shm_get_from_id function, which could lead to unauthorized access or privilege escalation.
Mitigation and Prevention
To mitigate the risks associated with CVE-2021-44733, it is essential to take immediate and long-term security measures.
Immediate Steps to Take
- Apply security patches provided by the Linux kernel maintainers promptly
- Monitor and restrict access to vulnerable systems
Long-Term Security Practices
- Regularly update the kernel and associated components
- Implement secure coding practices and code reviews to prevent similar vulnerabilities
Patching and Updates
- Keep the Linux kernel up-to-date with the latest security patches
- Follow vendor-specific security advisories for guidance on patch deployment