CVE-2020-29562

Publication date 4 December 2020

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

The iconv function in the GNU C Library (aka glibc or libc6) 2.30 to 2.32, when converting UCS4 text containing an irreversible character, fails an assertion in the code path and aborts the program, potentially resulting in a denial of service.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
eglibc	22.04 LTS jammy	Not in release
	21.10 impish	Not in release
	21.04 hirsute	Not in release
	20.10 groovy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not affected
glibc	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Not affected
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Fixed 2.31-0ubuntu9.7
	18.04 LTS bionic	Fixed 2.27-3ubuntu1.5
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not in release

Notes

mdeslaur

while bug reports indicate this was introduced in 2.30, there actually is a commit in 2.27 to fix the issue.

Patch details

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

Package	Patch details
glibc	Upstream: https://sourceware.org/git/?p=glibc.git;h=228edd356f03bf62dcf2b1335f25d43c602ee68d Upstream: https://sourceware.org/git/?p=glibc.git;h=5fa7884e25c5d11718253244fd1bc570c60f4cc8

Severity score breakdown

Parameter	Value
Base score	4.8 · Medium
Attack vector	Network
Attack complexity	High
Privileges required	Low
User interaction	Required
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-5310-1
GNU C Library vulnerabilities
1 March 2022