CVE-2020-6820
CVSS v3
8.1
HIGH
EPSS Score
5.0 %
exploit probability
CISA KEV
Yes
known exploited
Exploitation
—
SSVC status
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.
CISA Known Exploited Vulnerability
- Date Added
- 2021-11-03
- Patch Due Date
- 2022-05-03
- Ransomware Use
- Unknown
Technical details
- Published
- 2020-04-24
Frequently asked questions
What is CVE-2020-6820?
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.
Is CVE-2020-6820 actively exploited?
Yes. CVE-2020-6820 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 2022-05-03.
What is the CVSS score for CVE-2020-6820?
CVE-2020-6820 has a CVSS v3 base score of 8.1 (HIGH severity).
Is CVE-2020-6820 affecting your environment?
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