CVE-2021-44733

Related Vulnerabilities: CVE-2021-44733  

A use-after-free flaw in the Linux kernel TEE (Trusted Execution Environment) subsystem was found in the way user calls ioctl TEE_IOC_OPEN_SESSION or TEE_IOC_INVOKE. A local user could use this flaw to crash the system or escalate their privileges on the system. If the Linux system non configured with the CONFIG_PREEMPT option or CONFIG_CPU_SW_DOMAIN_PAN option enabled, then it is unlikely that a user can trigger this issue.

Description

A use-after-free flaw in the Linux kernel TEE (Trusted Execution Environment) subsystem was found in the way user calls ioctl TEE_IOC_OPEN_SESSION or TEE_IOC_INVOKE. A local user could use this flaw to crash the system or escalate their privileges on the system. If the Linux system non configured with the CONFIG_PREEMPT option or CONFIG_CPU_SW_DOMAIN_PAN option enabled, then it is unlikely that a user can trigger this issue.

Mitigation

To mitigate this issue, prevent the modules tee, trusted_tee from being loaded. Please see https://access.redhat.com/solutions/41278 for information on how to blacklist a kernel module to prevent it from loading automatically.

Additional Information

  • Bugzilla 2030747: CVE-2021-44733 kernel: use-after-free in the TEE subsystem
  • CWE-908: Use of Uninitialized Resource
  • FAQ: Frequently asked questions about CVE-2021-44733