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Time-of-check Time-of-use (TOCTOU) Race Condition

CVE-2021-31422

Severity High
Score 7.5/10

Summary

This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.1.1-49141. An attacker must first obtain the ability to execute high-privileged code on the target guest system in order to exploit this vulnerability. The specific flaw exists within the e1000e virtual device. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the hypervisor. Was ZDI-CAN-12527.

  • HIGH
  • LOCAL
  • HIGH
  • CHANGED
  • NONE
  • HIGH
  • HIGH
  • HIGH

CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

The software checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the software to perform invalid actions when the resource is in an unexpected state.

References

Advisory Timeline

  • Published