CVE-2021-36770

Publication date 9 August 2021

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

Encode.pm, as distributed in Perl through 5.34.0, allows local users to gain privileges via a Trojan horse Encode::ConfigLocal library (in the current working directory) that preempts dynamic module loading. Exploitation requires an unusual configuration, and certain 2021 versions of Encode.pm (3.05 through 3.11). This issue occurs because the || operator evaluates @INC in a scalar context, and thus @INC has only an integer value.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libencode-perl	24.10 oracular	Vulnerable
	24.04 LTS noble	Vulnerable
	23.10 mantic	Ignored end of life, was needed
	23.04 lunar	Ignored end of life, was needed
	22.10 kinetic	Ignored end of life, was needed
	22.04 LTS jammy	Vulnerable
	21.10 impish	Ignored end of life
	21.04 hirsute	Ignored end of life
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Needs evaluation
	14.04 LTS trusty	Not in release
perl	24.10 oracular	Fixed 5.32.1-3ubuntu3
	24.04 LTS noble	Fixed 5.32.1-3ubuntu3
	23.10 mantic	Fixed 5.32.1-3ubuntu3
	23.04 lunar	Fixed 5.32.1-3ubuntu3
	22.10 kinetic	Fixed 5.32.1-3ubuntu3
	22.04 LTS jammy	Fixed 5.32.1-3ubuntu3
	21.10 impish	Fixed 5.32.1-3ubuntu3
	21.04 hirsute	Fixed 5.32.1-3ubuntu2.1
	20.10 groovy	Ignored end of life
	20.04 LTS focal	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

mdeslaur

Introduced by change in Encode 3.05 in perl 5.32 and 5.34.

Patch details

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

Package	Patch details
perl	Upstream: c1a937f

Severity score breakdown

Parameter	Value
Base score	7.8 · High
Attack vector	Local
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H