CVE-2020-26979: Mozilla Firefox

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

When a user typed a URL in the address bar or the search bar and quickly hit the enter key, a website could sometimes capture that event and then redirect the user before navigation occurred to the desired, entered address. To construct a convincing spoof the attacker would have had to guess what the user was typing, perhaps by suggesting it. This vulnerability affects Firefox < 84.

Affected products

• Mozilla Firefox: before 84.0 (fixed in 84.0)

Published 2021-01-07. Last modified 2026-06-17.