CVE-2019-9815: High severity thunderbird vulnerability

Published May 21, 2019
·
Updated

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.

Other sources

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.

Affected Software

7 affected componentsFixes available
Mozilla Thunderbird<60.7
60.7
Mozilla Firefox<67
67
Mozilla Firefox ESR<60.7
60.7
Mozilla Firefox<67.0
Mozilla Firefox ESR<60.7
Mozilla Thunderbird<60.7
macOS

Event History

May 21, 2019
CVE Published
via Mozilla·12:00 AM
Jul 23, 2019
CVE Published
via MITRE·01:24 PM
Data Sourced
via MITRE·01:24 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2019-9815?

CVE-2019-9815 is a timing attack vulnerability that exists if hyperthreading is not disabled, similar to previous Spectre attacks.

2

Which software is affected by CVE-2019-9815?

Mozilla Firefox versions up to 67.0, Mozilla Firefox ESR versions up to 60.7, and Mozilla Thunderbird versions up to 60.7 are affected by CVE-2019-9815.

3

What is the severity of CVE-2019-9815?

The severity of CVE-2019-9815 is high with a CVSS score of 8.1.

4

How can I mitigate the CVE-2019-9815 vulnerability?

To mitigate CVE-2019-9815, it is recommended to update to Mozilla Firefox version 67.0, Mozilla Firefox ESR version 60.7, or Mozilla Thunderbird version 60.7.

5

Where can I find more information about CVE-2019-9815?

More information about CVE-2019-9815 can be found on the Mozilla Bugzilla website (https://bugzilla.mozilla.org/show_bug.cgi?id=1546544) and the Mozilla Security Advisories website (https://www.mozilla.org/en-US/security/advisories/mfsa2019-13/).

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