CVE-2020-12387

Description

A race condition when running shutdown code for Web Worker led to a use-after-free vulnerability. This resulted in a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.8, Firefox < 76, and Thunderbird < 68.8.0.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.00% Top 25%
Vendor Advisory ubuntu.com
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-18/ third party advisory
https://www.mozilla.org/security/advisories/mfsa2020-16/ third party advisory
https://www.mozilla.org/security/advisories/mfsa2020-17/ third party advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1545345 issue tracking permissions required
https://usn.ubuntu.com/4373-1/ vendor advisory broken link
https://security.gentoo.org/glsa/202005-03 third party advisory
https://security.gentoo.org/glsa/202005-04 third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-12387?
CVE-2020-12387 has been scored as a high severity vulnerability.
How to fix CVE-2020-12387?
To fix CVE-2020-12387, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-12387 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-12387 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-12387?
CVE-2020-12387 affects Mozilla Firefox ESR, Mozilla Firefox, Mozilla Thunderbird.
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