CVE-2025-10534Network attack vectorHinoki check available

Site identity spoofing via webpage-controlled WebRTC label

Published Sep 16, 2025 · Updated Sep 16, 2025

UI spoofing in Mozilla Firefox before 143 and Thunderbird before 143 allows remote attackers to falsify a macOS WebRTC sharing label. The WebRTC status-bar menu uses the webpage-controlled document title as its site label instead of displaying a trusted origin. A user must grant camera or microphone access and open the menu; the spoof obscures which site uses the device but does not alter the permission prompt.

CVSS severity8.1
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

UI spoofing in Mozilla Firefox before 143 and Thunderbird before 143 allows remote attackers to falsify a macOS WebRTC sharing label. The WebRTC status-bar menu uses the webpage-controlled document title as its site label instead of displaying a trusted origin. A user must grant camera or microphone access and open the menu; the spoof obscures which site uses the device but does not alter the permission prompt.

The record

CVE
CVE-2025-10534
Published
Sep 16, 2025
Updated
Sep 16, 2025
Vendor
Mozilla
Product
Firefox
Classifications
CWE-79, T1036
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 16, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <143

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mozilla · Firefoxversion=unspecified <143
Mozilla · Thunderbirdversion=unspecified <143

Published CVSS scores

8.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1036Masquerading

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo