CVE-2021-43531

MediumCVSS 4.3/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.1 4.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Weakness enumeration

CWE-346

Affected software

No affected versions have been published.

Timeline

Published: Dec 8, 2021
Last modified: Jun 17, 2026
NVD status: Modified

Related CVEs from 2021

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