CVE-2021-43530

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% 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

A Universal XSS vulnerability was present in Firefox for Android resulting from improper sanitization when processing a URL scanned from a QR code. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 94.

Affected products

Mozilla Firefox: before 94.0 — fixed in 94.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 94.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1736886
https://www.mozilla.org/security/advisories/mfsa2021-48/
https://bugzilla.mozilla.org/show_bug.cgi?id=1736886
https://www.mozilla.org/security/advisories/mfsa2021-48/

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