CVE-2024-4766Public exploitNetwork attack vector

UI spoofing via obscured fullscreen notification

Published May 14, 2024 · Updated Nov 26, 2024

UI spoofing in Mozilla Firefox for Android before 126 allows remote attackers to hide fullscreen warnings with crafted web content. A page that enters fullscreen can immediately invoke Android permission or Web Share dialogs, which cover the browser's fullscreen notification while fullscreen remains active. Exploitation requires user interaction with the crafted page and a convincing imitation of Firefox and Android chrome, limiting the consequence to user confusion and spoofing rather than direct data access.

CVSS severity4.3
Medium
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

UI spoofing in Mozilla Firefox for Android before 126 allows remote attackers to hide fullscreen warnings with crafted web content. A page that enters fullscreen can immediately invoke Android permission or Web Share dialogs, which cover the browser's fullscreen notification while fullscreen remains active. Exploitation requires user interaction with the crafted page and a convincing imitation of Firefox and Android chrome, limiting the consequence to user confusion and spoofing rather than direct data access.

The record

CVE
CVE-2024-4766
Published
May 14, 2024
Updated
Nov 26, 2024
Vendor
Mozilla
Product
Firefox
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 14, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 26, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <126

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <126

Published CVSS scores

4.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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