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Use After Free

CVE-2021-3929

High
8.2/10

Summary

A DMA reentrancy issue was found in the NVM Express Controller (NVME) emulation in QEMU prior to 7.0.0-rc0. This CVE is similar to CVE-2021-3750 and, just like it, when the reentrancy write triggers the reset function "nvme_ctrl_reset()", data structs will be freed leading to a use-after-free issue. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition or, potentially, executing arbitrary code within the context of the QEMU process on the host.

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

CWE-416 - Use After Free

Use-after-free (UaF) vulnerability occurs when the application is using a pointer to memory that has been freed. Any attempt to read/write to a buffer after it is de-allocated allows memory corruption, sensitive information exposure, and can potentially lead to arbitrary code execution.

References

Advisory Timeline

  • Published