CVE-2021-29962

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-06-24 · updated 2026-06-17
Weakness: CWE-404

Description

Firefox for Android would become unstable and hard-to-recover when a website opened too many popups. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 89.

Affected products

Mozilla Firefox: before 89.0 — fixed in 89.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 89.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1701673
https://www.mozilla.org/security/advisories/mfsa2021-23/
https://bugzilla.mozilla.org/show_bug.cgi?id=1701673
https://www.mozilla.org/security/advisories/mfsa2021-23/

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