CVE-2021-23959

An XSS bug in internal error pages could have led to various spoofing attacks, including other error pages and the address bar. Note: This issue only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 85.

• CWE-79

• https://bugzilla.mozilla.org/show_bug.cgi?id=1659035Issue Tracking, Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-03/Release Notes, Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1659035Issue Tracking, Permissions Required, Vendor Advisory
• https://www.mozilla.org/security/advisories/mfsa2021-03/Release Notes, Vendor Advisory

Published

Feb 26, 2021

Last Modified

Jun 17, 2026

Status

Modified

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