CVE-2020-12387: Use After Free

Published May 5, 2020
·
Updated

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash.

Affected Software

9 affected componentsFixes available
debian/firefox
130.0-2
debian/firefox-esr
115.14.0esr-1~deb11u1115.15.0esr-1~deb11u1115.14.0esr-1~deb12u1115.15.0esr-1~deb12u1115.15.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:115.15.0-1~deb11u11:115.12.0-1~deb12u11:115.15.0-1~deb12u11:128.1.1esr-11:128.2.0esr-1
Mozilla Thunderbird<68.8
68.8
Mozilla Firefox<76.0
Mozilla Firefox ESR<68.8.0
Mozilla Thunderbird<68.8.0
Mozilla Firefox<76
76
Mozilla Firefox ESR<68.8
68.8

Event History

May 5, 2020
CVE Published
12:00 AM
May 26, 2020
CVE Published
via MITRE·05:04 PM
Data Sourced
via MITRE·05:04 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:37 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:21 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2020-12387?

CVE-2020-12387 is classified as a medium severity vulnerability that can lead to a potential crash.

2

How do I fix CVE-2020-12387?

To fix CVE-2020-12387, upgrade to the latest versions of Firefox, Firefox ESR, or Thunderbird that contain the remediation.

3

Which versions are affected by CVE-2020-12387?

CVE-2020-12387 affects Mozilla Firefox versions up to 76, Firefox ESR up to 68.8, and Thunderbird versions up to 68.8.

4

What type of vulnerability is CVE-2020-12387?

CVE-2020-12387 is a use-after-free vulnerability caused by a race condition during the shutdown of Web Workers.

5

Can CVE-2020-12387 be exploited remotely?

CVE-2020-12387 may lead to a crash, which could potentially be exploited by an attacker under certain conditions.

Contact

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