CVE-2021-3748

Advisory lineage Upstream: 0 Downstream: 21
Modified
Published: 23 Mar 2022, 19:46
Last modified:03 Aug 2024, 17:09

Vulnerability Summary

Overall Risk (default)
medium
30/100
CVSS Score
7.5 HIGH
v3.1 (nvd)
EPSS Score
0.03% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

23 Mar 2022, 19:46
Published
Vulnerability first disclosed
03 Aug 2024, 17:09
Last Modified
Vulnerability information updated

Description

A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in a denial of service condition, or potentially execute code on the host with the privileges of the QEMU process.

CVSS Metrics

  • v3.1•HIGH•Score: 7.5CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
  • v2.0•MEDIUM•Score: 6.9AV:L/AC:M/Au:N/C:C/I:C/A:C

EPSS Trends

Current EPSS score: 0.03%• Percentile: 11%

Techniques & Countermeasures

  • CWE-416•Use After Free

    The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected Systems

  • canonical•ubuntu_linux

    18.04 | 20.04 | 21.10

  • debian•debian_linux

    9.0 | 10.0

  • fedoraproject•fedora

    34

  • qemu•qemu

    ≥ 0.10.0, < 6.2.0

  • redhat•enterprise_linux

    8.0

  • redhat•enterprise_linux_advanced_virtualization_eus

    8.4

References (8)