CVE-2021-29953
Mozilla: Universal Cross-Site Scripting
Severity
CriticalRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · May 5, 2021
Updated · November 22, 2025
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')