CVE-2025-24104: Apple iPadOS Privilege Escalation Flaw

CVE-2025-24104 Overview

CVE-2025-24104 is a symlink handling vulnerability affecting Apple iOS and iPadOS devices. The flaw exists in the backup restoration process, where improper handling of symbolic links allows a maliciously crafted backup file to modify protected system files. This vulnerability could enable an attacker to compromise system integrity by leveraging the backup restoration mechanism to bypass file system protections.

Critical Impact

Restoring a maliciously crafted backup file may lead to modification of protected system files, potentially compromising device integrity and security controls.

Affected Products

• Apple iPadOS versions prior to 17.7.4
• Apple iPadOS versions prior to 18.3
• Apple iOS (iPhone OS) versions prior to 18.3

Discovery Timeline

• 2025-01-27 - CVE-2025-24104 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2025-24104

Vulnerability Analysis

This vulnerability stems from improper handling of symbolic links (symlinks) during the iOS/iPadOS backup restoration process. The backup restoration mechanism failed to properly validate and sanitize symlinks contained within backup files, creating a path traversal-like attack vector through symlink following.

When a user restores a backup that has been maliciously crafted to include symbolic links pointing to protected system locations, the restoration process follows these symlinks without adequate validation. This allows attackers to write or modify files in protected system directories that should normally be inaccessible to user-controlled operations.

The attack requires local access and user interaction—specifically, the victim must restore a compromised backup file. This could occur through social engineering, where an attacker convinces a user to restore a backup from an untrusted source, or through compromise of backup storage locations.

Root Cause

The root cause is classified as CWE-59 (Improper Link Resolution Before File Access), commonly known as a "link following" vulnerability. The backup restoration component failed to implement proper symlink resolution checks before performing file operations. When processing backup contents, the system did not adequately verify whether symlinks in the backup pointed to locations outside the intended restoration scope, allowing the symlinks to be used as a mechanism to escape sandbox restrictions and access protected system files.

Attack Vector

The attack vector is local, requiring the attacker to either have physical access to the device or to convince the victim to restore a maliciously crafted backup file. The attack flow typically involves:

1. An attacker creates a malicious backup file containing symbolic links that point to protected system file locations
2. The victim obtains this backup through a compromised backup storage, social engineering, or other means
3. When the victim initiates a restore operation using this malicious backup, the system follows the embedded symlinks
4. The restoration process writes data to the symlink targets, effectively modifying protected system files

This vulnerability does not require any privileges on the target device but does require user interaction to initiate the restore process.

Detection Methods for CVE-2025-24104

Indicators of Compromise

• Unexpected modifications to system files following a backup restoration operation
• Presence of suspicious symbolic links in restored backup data pointing to system directories
• System integrity verification failures or unexpected file changes in protected locations
• Unusual system behavior or stability issues after restoring from external or untrusted backup sources

Detection Strategies

• Monitor backup restoration activities and log all file operations during the restore process
• Implement file integrity monitoring (FIM) on critical system files to detect unauthorized modifications
• Use mobile device management (MDM) solutions to track device configuration changes and backup restoration events
• Deploy endpoint detection solutions capable of identifying symlink-based attacks and path traversal attempts

Monitoring Recommendations

• Enable comprehensive logging for device backup and restoration activities
• Configure alerts for any modifications to protected system files or directories
• Implement security policies that restrict backup restoration from untrusted sources
• Regularly audit device configurations and system file integrity using enterprise MDM tools

How to Mitigate CVE-2025-24104

Immediate Actions Required

• Update all affected iOS devices to version 18.3 or later immediately
• Update all affected iPadOS devices to version 17.7.4 (for iPadOS 17.x) or 18.3 (for iPadOS 18.x) or later
• Avoid restoring backups from untrusted or unknown sources until devices are patched
• Review and audit any backup files before restoration if patching cannot be performed immediately

Patch Information

Apple has addressed this vulnerability with improved handling of symlinks in the backup restoration process. The fix is included in the following software versions:

• iPadOS 17.7.4 - For devices running the iPadOS 17.x branch
• iOS 18.3 - For iPhone devices
• iPadOS 18.3 - For iPad devices running the 18.x branch

For detailed patch information, refer to Apple Support Document #122066 and Apple Support Document #122067. Additional technical details are available in the Full Disclosure Announcement.

Workarounds

• Only restore backups from trusted and verified sources such as official iCloud backups or backups created on trusted computers
• Implement organizational policies restricting backup restoration from external media or unverified sources
• Use enterprise MDM solutions to control and monitor backup restoration capabilities on managed devices
• Consider disabling local backup restoration capabilities through MDM profiles until devices can be patched