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CVE-2020-6819

HIGH severity · CVSS 8.1 · CWE-362 · actively exploited (CISA KEV)
8.1CVSS HIGH exploited
Actively exploited in the wild (CISA Known Exploited Vulnerabilities). Added to KEV 2021-11-03. US federal agencies must patch by 2022-05-03.

Summary

Under certain conditions, when running the nsDocShell destructor, 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.

Impact & exploitability

Attack vectorNetwork
Attack complexityHigh
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
Exploit probability (EPSS)3%

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products we track (1)

Recommendation

This vulnerability is being actively exploited in the wild — patch affected products urgently. Open any affected product above for its exact safe version.