CVE-2019-20044

Publication date 24 February 2020

Last updated 18 August 2025

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

7.8 · High

Score breakdown

Description

In Zsh before 5.8, attackers able to execute commands can regain privileges dropped by the --no-PRIVILEGED option. Zsh fails to overwrite the saved uid, so the original privileges can be restored by executing MODULE_PATH=/dir/with/module zmodload with a module that calls setuid().

Read the notes from the security team

Status

Package Ubuntu Release Status
zsh 25.10 questing
Not affected
25.04 plucky
Not affected
24.10 oracular
Not affected
24.04 LTS noble
Not affected
23.10 mantic
Not affected
23.04 lunar
Not affected
22.10 kinetic
Not affected
22.04 LTS jammy
Needs evaluation
21.10 impish
Not affected
21.04 hirsute
Not affected
20.10 groovy
Not affected
20.04 LTS focal
Not affected
19.10 eoan Ignored end of life
18.04 LTS bionic
Fixed 5.4.2-3ubuntu3.2
16.04 LTS xenial
Fixed 5.1.1-1ubuntu2.3+esm1
14.04 LTS trusty Not in release

Get expanded security coverage with Ubuntu Pro

Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.

Get Ubuntu Pro 30-day free trial

Notes

mdeslaur

reproducer in debian bug low priority since upstream considers this to be a "minor vulnerability"

rodrigo-zaiden

affects versions prior to 5.8, so only xenial and bionic needed to be patched.

Patch details

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

Package Patch details
zsh

Severity score breakdown

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

References

Related Ubuntu Security Notices (USN)

Other references