CVE-2019-9815

Publication date 23 July 2019

Last updated 25 August 2025

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

8.1 · High

Score breakdown

Description

If hyperthreading is not disabled, a timing attack vulnerability exists, similar to previous Spectre attacks. Apple has shipped macOS 10.14.5 with an option to disable hyperthreading in applications running untrusted code in a thread through a new sysctl. Firefox now makes use of it on the main thread and any worker threads. *Note: users need to update to macOS 10.14.5 in order to take advantage of this change.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Read the notes from the security team

Status

Package Ubuntu Release Status
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
19.04 disco Ignored end of life
18.10 cosmic 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
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
19.04 disco Ignored end of life
18.10 cosmic Ignored end of life
18.04 LTS bionic Ignored
16.04 LTS xenial Not in release
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
19.04 disco Not in release
18.10 cosmic Not in release
18.04 LTS bionic Ignored
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
firefox 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
Not affected
21.10 impish
Not affected
21.04 hirsute
Not affected
20.10 groovy
Not affected
20.04 LTS focal Not in release
19.10 eoan
Not affected
19.04 disco
Not affected
18.10 cosmic
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty Not in release
thunderbird 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
Not affected
21.10 impish
Not affected
21.04 hirsute
Not affected
20.10 groovy
Not affected
20.04 LTS focal Not in release
19.10 eoan
Not affected
19.04 disco
Not affected
18.10 cosmic
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty Not in release

Notes

tyhicks

mozjs contains a copy of the SpiderMonkey JavaScript engine

chrisccoulson

MacOS only fix, as it depends on a MacOS only feature

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:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Other references

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