Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-3748

Use After Free

Published: Mar 23, 2022 | Modified: Nov 21, 2024
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS 2.x
6.9 MEDIUM
AV:L/AC:M/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
7.5 MODERATE
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-3748
CWEhttps://cwe.mitre.org/data/definitions/416.html

A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptors 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.

Weakness

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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.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 Software

NameVendorStart VersionEnd Version
QemuQemu0.10.0 (including)6.2.0 (excluding)
Advanced Virtualization for RHEL 8.2.1RedHatvirt:8.2-8020120211120005046.863bb0db*
Advanced Virtualization for RHEL 8.2.1RedHatvirt-devel:8.2-8020120211120005046.863bb0db*
Advanced Virtualization for RHEL 8.4.0.ZRedHatvirt:av-8040020211022000504.522a0ee4*
Advanced Virtualization for RHEL 8.4.0.ZRedHatvirt-devel:av-8040020211022000504.522a0ee4*
Red Hat Enterprise Linux 8RedHatvirt-devel:rhel-8060020220408104655.d63f516d*
Red Hat Enterprise Linux 8RedHatvirt:rhel-8060020220408104655.d63f516d*
QemuUbuntubionic*
QemuUbuntudevel*
QemuUbuntuesm-infra/bionic*
QemuUbuntuesm-infra/focal*
QemuUbuntufocal*
QemuUbuntuhirsute*
QemuUbuntuimpish*
QemuUbuntujammy*
QemuUbuntukinetic*
QemuUbuntutrusty*
QemuUbuntuxenial*

Potential Mitigations

References

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