VULNERABILITY INTELLIGENCE
CVE-2020-6820
CVSS score8.1 HIGH
EPSS probability7.06%
CISA KEVKnown exploited vulnerability
Published2020-04-24
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Known Exploited Vulnerability
Mozilla Firefox And Thunderbird Use-After-Free Vulnerability
Vendor / product: Mozilla / Firefox and Thunderbird
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.
Weakness classification
- nvd@nist.gov: CWE-362
- 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-362
Primary references
- security@mozilla.org — Issue Tracking, Permissions Required
- security@mozilla.org — Third Party Advisory
- security@mozilla.org — Vendor Advisory
- security@mozilla.org — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Permissions Required
- af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Vendor Advisory
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 — US Government Resource