CVE-2020-6819 (Mozilla Firefox and Thunderbird) is in the CISA Known Exploited Vulnerabilities catalog since 2021-11-03. Mozilla Firefox and Thunderbird contain a race condition vulnerability when running the nsDocShell… See the required fix, due date and advisories.
CVE-2020-6819 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 2021-11-03. Mozilla Firefox and Thunderbird contain a race condition vulnerability when running the nsDocShell destructor under certain conditions. The race condition creates a use-after-free vulnerability, causing unspecified impacts.
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Wording published by CISA for this catalog entry. It is the baseline action, not a decision about your environment: whether this exposure matters for you depends on where the affected component runs, what it is exposed to and who owns it.
A catalog entry tells you a vulnerability is being exploited somewhere. It does not tell you whether it matters in your estate, who owns the fix, or what evidence an auditor will ask for later. That is the work VulnTrek does: it takes findings from the tools you already run, decides which exposure actually matters, routes it to an owner, keeps remediation human-approved and retains the lineage as evidence.
Sourced from public upstream advisories (CISA KEV, ENISA EUVD, vendor PSIRTs) mirrored daily. Informational only — not a remediation decision, not legal advice, and the absence of a record is not evidence of safety.