CVE-2021-43531: Medium severity firefox vulnerability
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.
Affected Software
Event History
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
What is CVE-2021-43531?
CVE-2021-43531 is a vulnerability that allows a Web Extension in Mozilla Firefox to access the post-redirect URL of a clicked element in a Web Extensions context menu, potentially leaking sensitive data.
How does CVE-2021-43531 affect Mozilla Firefox?
CVE-2021-43531 affects Mozilla Firefox versions up to and excluding version 94.0.
What is the severity of CVE-2021-43531?
CVE-2021-43531 has a severity value of 4, indicating a medium severity.
How can I fix CVE-2021-43531?
To fix CVE-2021-43531, update Mozilla Firefox to version 94.0 or later.
Where can I find more information about CVE-2021-43531?
You can find more information about CVE-2021-43531 on the Mozilla Firefox website and in the Mozilla Security Advisory MFSB2021-48.