CVE-2023-28159Public exploitNetwork attack vector

UI spoofing via overlaid download dialogs

Published Jun 2, 2023 · Updated Jan 9, 2025

UI spoofing in Mozilla Firefox for Android before 111 allows remote attackers to conceal the fullscreen warning with download popups. The Android UI stack placed the fullscreen snackbar beneath download dialogs, allowing attacker-triggered popups to cover the origin-transition warning. A user must open a crafted page and enter fullscreen; the hidden warning can make the page resemble trusted browser or application chrome.

CVSS severity4.3
Medium
EPSS probability0.35%
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 111 allows remote attackers to conceal the fullscreen warning with download popups. The Android UI stack placed the fullscreen snackbar beneath download dialogs, allowing attacker-triggered popups to cover the origin-transition warning. A user must open a crafted page and enter fullscreen; the hidden warning can make the page resemble trusted browser or application chrome.

The record

CVE
CVE-2023-28159
Published
Jun 2, 2023
Updated
Jan 9, 2025
Vendor
Mozilla
Product
Firefox
Classifications
CWE-1021, T1036
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 2, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 9, 2025Record 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 <111

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <111

Published CVSS scores

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

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

CWE-1021Improper Restriction of Rendered UI Layers or Frames
T1036Masquerading

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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