8.1
High
Exploited
CVE-2020-6820 Mozilla Firefox And Thunderbird Use-After-Free Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply updates per vendor instructions.
Ransomware campaigns
Not observed so far
Weakness
CWE-362
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.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Thunderbird 68.7 | earliest → < 68.7.0 | 68.7.0 |
| Firefox 74.0 | earliest → < 74.0.1 | 74.0.1 |
| Firefox ESR 68.6 | earliest → < 68.6.1 | 68.6.1 |
References
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- bugzilla.mozilla.org bugzilla.mozilla.org
- USN-4335-1 usn.ubuntu.com
Timeline
- Published
- Added to the KEV catalogue
- Last modified
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