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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2020-6820 Detail

Description

Under certain conditions, when handling a ReadableStream, 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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1626728 CVE, Mozilla Corporation Issue Tracking  Permissions Required 
https://usn.ubuntu.com/4335-1/ CVE, Mozilla Corporation Third Party Advisory 
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-6820 CISA-ADP US Government Resource 
https://www.mozilla.org/security/advisories/mfsa2020-11/ CVE, Mozilla Corporation Vendor Advisory 
https://www.mozilla.org/security/advisories/mfsa2020-14/ CVE, Mozilla Corporation Vendor Advisory 

This CVE is in CISA's Known Exploited Vulnerabilities Catalog

Reference CISA's BOD 22-01 and Known Exploited Vulnerabilities Catalog for further guidance and requirements.

Vulnerability Name Date Added Due Date Required Action
Mozilla Firefox And Thunderbird Use-After-Free Vulnerability 11/03/2021 05/03/2022 Apply updates per vendor instructions.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') cwe source acceptance level NIST   CISA-ADP  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

12 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2020-6820
NVD Published Date:
04/24/2020
NVD Last Modified:
11/04/2025
Source:
Mozilla Corporation