CVE-2021-20203

Publication date 25 February 2021

Last updated 9 June 2026

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

3.2 · Low

Score breakdown

Description

An integer overflow issue was found in the vmxnet3 NIC emulator of the QEMU for versions up to v5.2.0. It may occur if a guest was to supply invalid values for rx/tx queue size or other NIC parameters. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

Status

Package Ubuntu Release Status
qemu 26.04 LTS resolute
Fixed 1:6.2+dfsg-2ubuntu5
25.10 questing
Fixed 1:6.2+dfsg-2ubuntu5
25.04 plucky
Fixed 1:6.2+dfsg-2ubuntu5
24.10 oracular
Fixed 1:6.2+dfsg-2ubuntu5
24.04 LTS noble
Fixed 1:6.2+dfsg-2ubuntu5
23.10 mantic
Fixed 1:6.2+dfsg-2ubuntu5
23.04 lunar
Fixed 1:6.2+dfsg-2ubuntu5
22.10 kinetic
Fixed 1:6.2+dfsg-2ubuntu5
22.04 LTS jammy
Fixed 1:6.2+dfsg-2ubuntu5
21.10 impish
Fixed 1:6.0+dfsg-2expubuntu1.2
21.04 hirsute Ignored end of life
20.10 groovy Ignored end of life
20.04 LTS focal
Fixed 1:4.2-3ubuntu6.21
18.04 LTS bionic
Fixed 1:2.11+dfsg-1ubuntu7.39
16.04 LTS xenial
Fixed 1:2.5+dfsg-5ubuntu10.51+esm4
14.04 LTS trusty
Fixed 2.0.0+dfsg-2ubuntu1.47+esm6

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Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
qemu

Severity score breakdown

Parameter Value
Base score 3.2 · Low
Attack vector Local
Attack complexity Low
Privileges required High
User interaction None
Scope Changed
Confidentiality None
Integrity impact None
Availability impact Low
Vector CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

Other references

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