CVE-2021-29975

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-05 · updated 2026-06-17

Description

Through a series of DOM manipulations, a message, over which the attacker had control of the text but not HTML or formatting, could be overlaid on top of another domain (with the new domain correctly shown in the address bar) resulting in possible user confusion. This vulnerability affects Firefox < 90.

Affected products

Mozilla Firefox: before 90.0 — fixed in 90.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 90.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1713259
https://security.gentoo.org/glsa/202202-03
https://www.mozilla.org/security/advisories/mfsa2021-28/
https://bugzilla.mozilla.org/show_bug.cgi?id=1713259
https://security.gentoo.org/glsa/202202-03
https://www.mozilla.org/security/advisories/mfsa2021-28/

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