VULNERABILITY INTELLIGENCE

CVE-2021-32846

CVSS score7.7 HIGH
EPSS probability0.32%
CISA KEVNot currently listed
Published2023-02-17
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Description

HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107, function `pci_vtsock_proc_tx` in `virtio-sock` can lead to to uninitialized memory use. In this situation, there is a check for the return value to be less or equal to `VTSOCK_MAXSEGS`, but that check is not sufficient because the function can return `-1` if it finds an error it cannot recover from. Moreover, the negative return value will be used by `iovec_pull` in a while condition that can further lead to more corruption because the function is not designed to handle a negative `iov_len`. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit af5eba2360a7351c08dfd9767d9be863a50ebaba.

Weakness classification

  • CWE-754: Improper Check for Unusual or Exceptional Conditions
  • CWE-908: Use of Uninitialized Resource

Primary references