Connect your agent
AdvisoriesCriticalCheck your lockfilePluginHow it worksPricing Connect your agent

CVE record · CVE-2020-6820

Race condition in Mozilla Thunderbird and others

CVSS 8.1 HighCriticalIn CISA KEVEPSS 0.071 · 94th percentile

Critical, because:

  • In CISA’s KEV catalogue since 3 Nov 2021: it is known to be exploited.

How we decide what’s critical

Published by the CVE Program (CNA: mozilla) at 24 Apr 2020, 15:56 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
VendorProductVersions
Mozilla Thunderbird
  • affected unspecified to before 68.7.0 custom
Mozilla Firefox
  • affected unspecified to before 74.0.1 custom
Mozilla Firefox ESR
  • affected unspecified to before 68.6.1 custom
Identifiers
CVE-2020-6820
CNA
mozilla
Weakness (CWE)
CWE-362
Tags
Published
24 Apr 2020
Updated
21 Oct 2025

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

ScoreRatingCVSSVectorSource
8.1 High 3.1 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H ADP (CISA-ADP)
  • CISA KEV Listed since 3 Nov 2021: known to be exploited.
  • EPSS 0.071, the 94th percentile, on 8 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 24 Apr 2020. New records show when each source confirmed them.

Sources

References from the CNA

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.