CVE-2020-6820
Last modified
CVE-2020-6820 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. 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. CISA has confirmed active exploitation in the wild. EPSS estimates a 6.30% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitation Status
This vulnerability is listed in CISA’s Known Exploited Vulnerabilities catalog, confirming active exploitation in the wild. Federal agencies must remediate by .
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 68.6.1 |
| Mozilla | Firefox | < 74.0.1 |
| Mozilla | Thunderbird | < 68.7.0 |
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1626728Issue Tracking, Permissions Required
- https://usn.ubuntu.com/4335-1/Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-11/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-14/Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1626728Issue Tracking, Permissions Required
- https://usn.ubuntu.com/4335-1/Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-11/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2020-14/Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-6820US Government Resource
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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