Back to CVE Browser

CVE-2020-6819

Known Exploited (CISA KEV)HIGH

8.1

CVSS Severity Score

EPSS Score71.4860%

EPSS Percentile98.13th

PublishedApr 24, 2020

Last ModifiedNov 4, 2025

Vulnerability Description

Under certain conditions, when running the nsDocShell destructor, a race condition can cause a use-after-free. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Thunderbird < 68.7.0, Firefox < 74.0.1, and Firefox ESR < 68.6.1.

Affected Platforms (CPE)

📦

Mozilla

Firefox

< 68.6.1

📦

Mozilla

Firefox

< 74.0.1

📦

Mozilla

Thunderbird

< 68.7.0

References & Advisories

🔗 https://bugzilla.mozilla.org/show_bug.cgi?id=1620818

🔗 https://usn.ubuntu.com/4335-1/

🔗 https://www.mozilla.org/security/advisories/mfsa2020-11/

🔗 https://www.mozilla.org/security/advisories/mfsa2020-14/

🔗 https://bugzilla.mozilla.org/show_bug.cgi?id=1620818

🔗 https://usn.ubuntu.com/4335-1/

🔗 https://www.mozilla.org/security/advisories/mfsa2020-11/

🔗 https://www.mozilla.org/security/advisories/mfsa2020-14/

Related Vulnerabilities

CVE-2019-1170810.0

Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the no...

CVE-2019-2513610.0

A compromised child process could have injected XBL Bindings into privileged CSS rules, resulting in arbitrary code execution and ...

CVE-2018-1850510.0

An earlier fix for an Inter-process Communication (IPC) vulnerability, CVE-2011-3079, added authentication to communication betwee...

CVE-2020-1238810.0

The Firefox content processes did not sufficiently lockdown access control which could result in a sandbox escape. *Note: this iss...