CVE-2020-6820

8.1 HIGH CISA KEV - Actively Exploited
Published: April 24, 2020 Modified: November 04, 2025
View on NVD

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1626728
Source: security@mozilla.org
Issue Tracking Permissions Required
https://usn.ubuntu.com/4335-1/
Source: security@mozilla.org
Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-11/
Source: security@mozilla.org
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-14/
Source: security@mozilla.org
Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1626728
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Permissions Required
https://usn.ubuntu.com/4335-1/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2020-11/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-14/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-6820
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

9 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.1 / 10.0
EPSS (Exploit Probability)
5.0%
89th percentile
Exploitation Status
Actively Exploited
Remediation due: 2022-05-03

Weaknesses (CWE)

CWE-362 CWE-362

Affected Vendors

mozilla

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