CVE-2020-12387

Publication date 6 May 2020

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

8.1 · High

Score breakdown

Description

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

Read the notes from the security team

Status

Package Ubuntu Release Status
firefox 24.04 LTS noble
Fixed 76.0+build2-0ubuntu1
23.10 mantic
Fixed 76.0+build2-0ubuntu1
23.04 lunar
Fixed 76.0+build2-0ubuntu1
22.10 kinetic
Fixed 76.0+build2-0ubuntu1
22.04 LTS jammy
Fixed 76.0+build2-0ubuntu1
21.10 impish
Fixed 76.0+build2-0ubuntu1
21.04 hirsute
Fixed 76.0+build2-0ubuntu1
20.10 groovy
Fixed 76.0+build2-0ubuntu1
20.04 LTS focal
Fixed 76.0+build2-0ubuntu0.20.04.1
19.10 eoan
Fixed 76.0+build2-0ubuntu0.19.10.1
18.04 LTS bionic
Fixed 76.0+build2-0ubuntu0.18.04.1
16.04 LTS xenial
Fixed 76.0+build2-0ubuntu0.16.04.1
14.04 LTS trusty Not in release
mozjs38 24.04 LTS noble Not in release
23.10 mantic Not in release
23.04 lunar Not in release
22.10 kinetic Not in release
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
19.10 eoan Not in release
18.04 LTS bionic Ignored
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
mozjs52 24.04 LTS noble Not in release
23.10 mantic Not in release
23.04 lunar Not in release
22.10 kinetic Not in release
22.04 LTS jammy Not in release
21.10 impish Not in release
21.04 hirsute Not in release
20.10 groovy Ignored end of life
20.04 LTS focal Ignored
19.10 eoan Ignored end of life
18.04 LTS bionic Ignored
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
thunderbird 24.04 LTS noble
Fixed 1:68.8.0+build2-0ubuntu1
23.10 mantic
Fixed 1:68.8.0+build2-0ubuntu1
23.04 lunar
Fixed 1:68.8.0+build2-0ubuntu1
22.10 kinetic
Fixed 1:68.8.0+build2-0ubuntu1
22.04 LTS jammy
Fixed 1:68.8.0+build2-0ubuntu1
21.10 impish
Fixed 1:68.8.0+build2-0ubuntu1
21.04 hirsute
Fixed 1:68.8.0+build2-0ubuntu1
20.10 groovy
Fixed 1:68.8.0+build2-0ubuntu1
20.04 LTS focal
Fixed 1:68.8.0+build2-0ubuntu0.20.04.2
19.10 eoan
Fixed 1:68.8.0+build2-0ubuntu0.19.10.2
18.04 LTS bionic
Fixed 1:68.8.0+build2-0ubuntu0.18.04.2
16.04 LTS xenial
Fixed 1:68.8.0+build2-0ubuntu0.16.04.2
14.04 LTS trusty Not in release
mozjs68 24.04 LTS noble Not in release
23.10 mantic Not in release
23.04 lunar Not in release
22.10 kinetic Not in release
22.04 LTS jammy Not in release
21.10 impish Not in release
21.04 hirsute Not in release
20.10 groovy Ignored end of life
20.04 LTS focal Ignored
19.10 eoan Not in release
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
mozjs60 24.04 LTS noble Not in release
23.10 mantic Not in release
23.04 lunar Not in release
22.10 kinetic Not in release
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
19.10 eoan Ignored end of life
18.04 LTS bionic Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release

Notes

tyhicks

mozjs contains a copy of the SpiderMonkey JavaScript engine

Severity score breakdown

Parameter Value
Base score 8.1 · High
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

Other references