CVE-2021-43544

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-12-08 · updated 2026-06-17
Weakness: CWE-79

Description

When receiving a URL through a SEND intent, Firefox would have searched for the text, but subsequent usages of the address bar might have caused the URL to load unintentionally, which could lead to XSS and spoofing attacks. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 95.

Affected products

Mozilla Firefox: before 95.0 — fixed in 95.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 95.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1739934
https://www.mozilla.org/security/advisories/mfsa2021-52/
https://bugzilla.mozilla.org/show_bug.cgi?id=1739934
https://www.mozilla.org/security/advisories/mfsa2021-52/

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