CVE-2024-54503: Apple iPadOS Call Mute State Vulnerability

CVE-2024-54503 Overview

CVE-2024-54503 is a user interface inconsistency affecting Apple iOS and iPadOS. Muting a call while the device is still ringing may not actually enable the mute function. The user interface indicates the call is muted, but audio from the microphone can still be transmitted. Apple addressed the issue through improved state management in iOS 18.2 and iPadOS 18.2.

The flaw is categorized under [CWE-NVD-noinfo] and falls into the User Interface Confusion class of weaknesses. Exploitation requires user interaction and specific timing conditions, which limits practical abuse but creates privacy exposure for affected users.

Critical Impact
An attacker or eavesdropper on an active call could capture audio the user believed was muted, resulting in unintended disclosure of private conversations.

Affected Products

Apple iOS versions prior to 18.2
Apple iPadOS versions prior to 18.2
Apple iPhone and iPad devices running vulnerable firmware

Discovery Timeline

2024-12-12 - CVE-2024-54503 published to the National Vulnerability Database
2024-12-12 - Apple publishes security content for iOS 18.2 and iPadOS 18.2
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-54503

Vulnerability Analysis

The vulnerability resides in the call-handling user interface of iOS and iPadOS. When a user taps the mute control while an incoming or outgoing call is still in the ringing state, the UI reflects a muted condition but the audio pipeline does not transition into the muted state. Once the call connects, microphone input continues to be transmitted to the remote party despite the on-screen indicator.

The discrepancy is a state synchronization defect between the UI layer and the underlying audio session state machine. Apple's advisory describes the fix as "improved state management," indicating the audio subsystem now correctly honors mute requests issued during the pre-connection phase of a call.

The issue results in confidentiality exposure of spoken audio but does not grant code execution, data modification, or persistence capabilities on the device.

Root Cause

The root cause is improper handling of mute state transitions during the ringing phase of a call session. The audio session component did not persist or apply the mute flag set before the call entered an active state, leaving the microphone unmuted after connection.

Attack Vector

Exploitation is passive from the attacker perspective. The remote party on a call receives audio the local user intended to suppress. Triggering the condition requires the local user to toggle mute during the ringing window, a timing-dependent user action that limits reliable exploitation. The CVSS vector reflects network reachability with high attack complexity and required user interaction.

The vulnerability affects only local audio confidentiality. There is no path to code execution, privilege escalation, or integrity impact.

Detection Methods for CVE-2024-54503

Indicators of Compromise

No forensic indicators are produced by this flaw because exploitation does not generate log entries or artifacts on the device.
User reports of audio captured on calls that were believed to be muted on iOS or iPadOS 18.1 and earlier.
Devices in enterprise fleets running iOS or iPadOS below 18.2 as reported by mobile device management (MDM) inventory.

Detection Strategies

Query MDM platforms for the installed OS version on all managed iPhone and iPad devices.
Flag devices reporting iOS or iPadOS versions below 18.2 for remediation.
Correlate user-submitted privacy incidents involving call audio with device OS version data.

Monitoring Recommendations

Maintain continuous OS version telemetry through MDM compliance policies.
Track Apple security advisory releases referenced in the Apple Support Article for related call-handling fixes.
Review user privacy complaints tied to voice calls on managed devices.

How to Mitigate CVE-2024-54503

Immediate Actions Required

Update all affected iPhone and iPad devices to iOS 18.2 or iPadOS 18.2 or later.
Enforce minimum OS version compliance policies through MDM.
Inform users that pre-connection mute actions may not be honored on unpatched devices.

Patch Information

Apple released fixes in iOS 18.2 and iPadOS 18.2 on December 11, 2024. Details are documented in the Apple Support Article and the corresponding Full Disclosure Mailing List post. The fix implements improved state management in the call audio subsystem.

Workarounds

Wait until a call is fully connected before toggling the mute control.
Verify audio is actually muted by observing the remote party or using a secondary test call before discussing sensitive matter.
Restrict use of unpatched devices for calls involving confidential conversations until updates are applied.

bash

# Verify installed iOS/iPadOS version via MDM query or device Settings
# Settings > General > About > Software Version
# Required minimum: 18.2