CVE-2021-31870

Publication date 30 April 2021

Last updated 25 August 2025

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

9.8 · Critical

Score breakdown

Description

An issue was discovered in klibc before 2.0.9. Multiplication in the calloc() function may result in an integer overflow and a subsequent heap buffer overflow.

Read the notes from the security team

Status

Package Ubuntu Release Status
klibc 22.04 LTS jammy
Not affected
21.10 impish
Not affected
21.04 hirsute Ignored end of life
20.10 groovy Ignored end of life
20.04 LTS focal
Fixed 2.0.7-1ubuntu5.1
18.04 LTS bionic
Fixed 2.0.4-9ubuntu2.1
16.04 LTS xenial
Fixed 2.0.4-8ubuntu1.16.04.4+esm1
14.04 LTS trusty
Fixed 2.0.3-0ubuntu1.14.04.3+esm2

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Notes

mdeslaur

only used in initramfs, doesn't parse untrusted data

Patch details

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

Package Patch details
klibc

Severity score breakdown

Parameter Value
Base score 9.8 · Critical
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

Other references