CVE-2020-6820

Summary

CVECVE-2020-6820
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2020-04-24 16:15:00 UTC
Updated2022-07-12 17:42:00 UTC
DescriptionUnder 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.

Risk And Classification

EPSS: 0.031300000 probability, percentile 0.867990000 (date 2026-04-01)

CISA KEV: Listed on 2021-11-03; due 2022-05-03; ransomware use Unknown

Problem Types: CWE-362

CISA Known Exploited Vulnerability

VendorMozilla
ProductFirefox and Thunderbird
NameMozilla Firefox And Thunderbird Use-After-Free Vulnerability
Required ActionApply updates per vendor instructions.
Noteshttps://nvd.nist.gov/vuln/detail/CVE-2020-6820

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Mozilla Firefox All All All All
Application Mozilla Firefox All All All All
Application Mozilla Firefox Esr All All All All
Application Mozilla Firefox Esr All All All All
Application Mozilla Thunderbird All All All All
Application Mozilla Thunderbird All All All All

References

ReferenceSourceLinkTags
Security Vulnerabilities fixed in Firefox 74.0.1 and Firefox ESR 68.6.1 — Mozilla MISC www.mozilla.org Vendor Advisory
Access Denied MISC bugzilla.mozilla.org Issue Tracking, Permissions Required
USN-4335-1: Thunderbird vulnerabilities | Ubuntu security notices UBUNTU usn.ubuntu.com Third Party Advisory
Security Vulnerabilities fixed in Thunderbird 68.7.0 — Mozilla MISC www.mozilla.org Vendor Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
CISA Known Exploited Vulnerabilities catalog CISA www.cisa.gov kev

Legacy QID Mappings

  • 296074 Oracle Solaris 11.4 Support Repository Update (SRU) 22.69.4 Missing (CPUAPR2020)
  • 376946 Alibaba Cloud Linux Security Update for firefox (ALINUX2-SA-2020:0085)
  • 500928 Alpine Linux Security Update for firefox-esr
  • 500947 Alpine Linux Security Update for firefox
  • 501077 Alpine Linux Security Update for mozjs68
  • 502373 Alpine Linux Security Update for thunderbird
  • 503832 Alpine Linux Security Update for firefox
  • 505441 Alpine Linux Security Update for thunderbird
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