CVE-2021-23959

MediumCVSS 6.1/10Last modified Jun 17, 2026

Description

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.

Metrics

CVSS 3.1 6.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness enumeration

CWE-79

Affected software

Vendor	Product	Versions
Mozilla	Firefox	< 85

References

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

Timeline

Published: Feb 26, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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