CVE-2021-23973

Description

When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted, and the content of that error may have revealed information about the resource. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.54%
Vendor Advisory debian.org 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
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox ESR
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-07/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-09/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-08/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1690976 vendor advisory issue tracking permissions required
https://lists.debian.org/debian-lts-announce/2021/03/msg00000.html third party advisory mailing list
https://www.debian.org/security/2021/dsa-4866 third party advisory vendor advisory
https://security.gentoo.org/glsa/202104-10 third party advisory vendor advisory
https://security.gentoo.org/glsa/202104-09 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-23973?
CVE-2021-23973 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23973?
To fix CVE-2021-23973, 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-2021-23973 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-23973 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-2021-23973?
CVE-2021-23973 affects Mozilla Firefox, Mozilla Thunderbird, Mozilla Firefox ESR.
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