CVE-2021-29953

MediumCVSS 6.1/10Last modified Jun 17, 2026

Description

A malicious webpage could have forced a Firefox for Android user into executing attacker-controlled JavaScript in the context of another domain, resulting in a Universal Cross-Site Scripting vulnerability. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected. Further details are being temporarily withheld to allow users an opportunity to update.*. This vulnerability affects Firefox < 88.0.1 and Firefox for Android < 88.1.3.

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	>= unspecified, < 88.0.1
Mozilla	Firefox for Android	>= unspecified, < 88.1.3

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1701684Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-20/Release Notes, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1701684Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-20/Release Notes, Vendor Advisory

Timeline

Published: Jun 24, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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