CVE-2020-15656: Critical severity Mozilla Firefox vulnerability

Published Jul 28, 2020
·
Updated

JIT optimizations involving the Javascript arguments object could confuse later optimizations. This risk was already mitigated by various precautions in the code, resulting in this bug rated at only moderate severity.

Affected Software

12 affected componentsFixes available
Mozilla Firefox<79.0
Mozilla Firefox ESR<78.1
Mozilla Thunderbird<78.1
openSUSE Leap=15.2
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=20.04
Mozilla Thunderbird<78.1
78.1
Mozilla Firefox<79
79
Mozilla Firefox ESR<78.1
78.1
debian/firefox
148.0.2-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.8.0esr-1~deb11u11:140.6.0esr-1~deb12u11:140.8.0esr-1~deb12u11:140.6.0esr-1~deb13u11:140.8.0esr-1~deb13u11:140.8.0esr-1

Event History

Jul 28, 2020
CVE Published
via Mozilla·12:00 AM
Aug 10, 2020
CVE Published
via MITRE·05:43 PM
Data Sourced
via MITRE·05:43 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:43 PM
Description
Feb 23, 2026
Data Sourced
via Ubuntu·07:56 PM
RemedyDescriptionSeverityAffected Software
Mar 11, 2026
Data Sourced
via Debian·08:11 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2020-15656?

The severity of CVE-2020-15656 is rated as moderate.

2

Which software products are affected by CVE-2020-15656?

Mozilla Firefox ESR 78.1, Mozilla Thunderbird 78.1, and Mozilla Firefox up to version 79 are affected by CVE-2020-15656.

3

How can I mitigate the risk of CVE-2020-15656?

Apply the recommended remedy versions: Mozilla Firefox ESR 78.1, Mozilla Thunderbird 78.1, and Mozilla Firefox version up to 79.

4

Where can I find more information about CVE-2020-15656?

You can find more information about CVE-2020-15656 on the following references: [Bugzilla Mozilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1647293), [Mozilla Security Advisory mfsa2020-33](https://www.mozilla.org/en-US/security/advisories/mfsa2020-33/), [Mozilla Security Advisory mfsa2020-30](https://www.mozilla.org/en-US/security/advisories/mfsa2020-30/)

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