CVE-2021-43531

Description

When a user loaded a Web Extensions context menu, the Web Extension could access the post-redirect URL of the element clicked. If the Web Extension lacked the WebRequest permission for the hosts involved in the redirect, this would be a same-origin-violation leaking data the Web Extension should have access to. This was fixed to provide the pre-redirect URL. This is related to CVE-2021-43532 but in the context of Web Extensions. This vulnerability affects Firefox < 94.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.14%
Vendor Advisory mozilla.org Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2021-48/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1659155 issue tracking permissions required vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-43531?
CVE-2021-43531 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43531?
To fix CVE-2021-43531, 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-2021-43531 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43531 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-2021-43531?
CVE-2021-43531 affects Mozilla Firefox.
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