CVE-2021-29944: Mozilla Firefox

Medium severity, CVSS 6.1. EPSS: 0.7% chance of exploitation in the next 30 days.

Lack of escaping allowed HTML injection when a webpage was viewed in Reader View. While a Content Security Policy prevents direct code execution, HTML injection is still possible. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 88.

Affected products

• Mozilla Firefox: before 88.0 (fixed in 88.0)

Published 2021-06-24. Last modified 2026-06-17.