CVE-2021-29953

6.1 mediumEPSS 0.6%

Medium (6.1) in mozilla firefox. EPSS 0.6% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

6.1 medium

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS: 0.6% chance of exploitation in the next 30 days; higher than 51% of CVEs (scores of 2026-10-31)
CWE: CWE-79
Published: 2021-06-24
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mozilla:firefox

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1701684
https://www.mozilla.org/security/advisories/mfsa2021-20/
https://bugzilla.mozilla.org/show_bug.cgi?id=1701684
https://www.mozilla.org/security/advisories/mfsa2021-20/

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