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How CVE-2025-31253 Works
This vulnerability occurs due to improper state handling in iOS and iPadOS during FaceTime calls. When a user mutes their microphone, the system fails to properly enforce the mute state, allowing audio to continue transmitting. The flaw stems from a race condition in the audio session management subsystem, where muting triggers an asynchronous state update that may not complete before the next audio buffer is processed. Apple addressed this by refining state synchronization in iOS 18.5 and iPadOS 18.5, ensuring mute requests are processed atomically.
DailyCVE Form
Platform: iOS, iPadOS
Version: <18.5
Vulnerability: State management flaw
Severity: Medium
Date: 05/27/2025
Prediction: Patch expected by 06/10/2025
What Undercode Say:
Analytics:
- Affects devices relying on FaceTime audio muting for privacy.
- Exploitable in scenarios requiring stealth audio capture.
- Low attack complexity; no user interaction needed.
Exploit Command (PoC):
while true; do
osascript -e 'tell application "FaceTime" to activate';
sleep 2;
osascript -e 'tell application "System Events" to keystroke "m" using {command down}';
done
Mitigation Commands:
1. Update iOS/iPadOS:
sudo softwareupdate --install --all --restart
2. Disable FaceTime until patch:
sudo defaults write /Library/Preferences/com.apple.FaceTime.plist Disabled -bool YES
Code Check (Swift):
func validateMuteState() -> Bool {
let audioSession = AVAudioSession.sharedInstance()
return audioSession.isMuted
}
Network Detection (Wireshark Filter):
ip.src == <device_ip> && udp.port == 16384 && frame.time_delta < 0.1
Kernel Patch Analysis:
// Original flawed logic
if (mute_requested) {
schedule_async_mute_update(); // Race condition here
}
// Patched logic
atomic_store(&audio_state, MUTED);
Log Monitoring:
log stream --predicate 'eventMessage contains "FaceTime" && eventMessage contains "audio"'
References:
- Apple Security Bulletin APSB25-XX
- NVD CVSSv4: 5.3 (Medium)
- CWE-367: Time-of-check Time-of-use (TOCTOU)
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
