CVE-2021-23998

Description

Through complicated navigations with new windows, an HTTP page could have inherited a secure lock icon from an HTTPS page. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.22%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox ESR
Affected: Mozilla Thunderbird
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-14/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-16/ release notes vendor advisory
https://www.mozilla.org/security/advisories/mfsa2021-15/ release notes vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1667456 vendor advisory issue tracking permissions required

Frequently Asked Questions

What is the severity of CVE-2021-23998?
CVE-2021-23998 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23998?
To fix CVE-2021-23998, 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-2021-23998 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-23998 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23998?
CVE-2021-23998 affects Mozilla Firefox ESR, Mozilla Thunderbird, Mozilla Firefox.
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