CVE-2020-6820
Mozilla Firefox And Thunderbird Use-After-Free Vulnerability
8.1
HIGH
CVSS 3.1
⚠ KEVEPSS 3.1%
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.
How to fix CVE-2020-6820
To remediate CVE-2020-6820, upgrade the affected package to a fixed version below.
- —upgrade to 68.6.1esr-1 or later
- —upgrade to 1:68.7.0-1 or later
Is CVE-2020-6820 being exploited?
Yes — CVE-2020-6820 is on the CISA Known Exploited Vulnerabilities (KEV) catalog. Patch immediately.
Affected packages (2)
- from 0, < 68.6.1esr-1
- from 0, < 1:68.7.0-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |