CVE-2020-12420

Public Exploit

Description

When trying to connect to a STUN server, a race condition could have caused a use-after-free of a pointer, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Firefox ESR < 68.10, Firefox < 78, and Thunderbird < 68.10.0.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory opensuse.org Vendor Advisory ubuntu.com Vendor Advisory gentoo.org Vendor Advisory gentoo.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Firefox
Affected: Mozilla Thunderbird
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-24/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-26/ vendor advisory
https://www.mozilla.org/security/advisories/mfsa2020-25/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1643437 issue tracking exploit vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00023.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00026.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00027.html mailing list third party advisory vendor advisory
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00049.html mailing list third party advisory vendor advisory
https://usn.ubuntu.com/4421-1/ third party advisory vendor advisory
https://security.gentoo.org/glsa/202007-09 third party advisory vendor advisory
https://security.gentoo.org/glsa/202007-10 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2020-12420?
CVE-2020-12420 has been scored as a high severity vulnerability.
How to fix CVE-2020-12420?
To fix CVE-2020-12420, 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-2020-12420 being actively exploited in the wild?
It is possible that CVE-2020-12420 is being exploited or will be exploited in a near future based on public information. 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-2020-12420?
CVE-2020-12420 affects Mozilla Firefox ESR, Mozilla Firefox, Mozilla Thunderbird.
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