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Double Free

CVE-2021-3492

Severity High
Score 7.8/10

Summary

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.

  • LOW
  • LOCAL
  • HIGH
  • UNCHANGED
  • NONE
  • LOW
  • HIGH
  • HIGH

CWE-415 - Double Free

The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations.

References

Advisory Timeline

  • Published