CVE-2025-30431

Executive Summary

CVE-2025-30431 is a vulnerability in Apple macOS that allows a malicious application to access private information. The flaw exists in the operating system's core security model, where insufficient checks permit an app to bypass sandbox restrictions or privacy controls. The vulnerability has been patched in macOS Sequoia 15.4, macOS Sonoma 14.7.5, and macOS Ventura 13.7.5. No public proof-of-concept (PoC) or exploit code is currently available, and the CVSS score has not been assigned. The EPSS score is 0.0%, indicating a very low probability of exploitation in the wild at this time.

Supply Chain & Package Security

This vulnerability is not related to any open-source package manager (NPM, PyPI, Go, Ruby). It is a native macOS operating system vulnerability. The attack vector requires a user to execute a malicious application, which could be distributed through social engineering, phishing, or compromised software downloads.

CVSS Breakdown & Threat Level

The CVSS score for this CVE has not been officially assigned by NVD. Based on the description and impact, a reasonable assessment would be:

• Attack Vector (AV): Local (L) - The attacker must have the ability to execute a malicious app on the target system.
• Attack Complexity (AC): Low (L) - No special conditions are required to exploit the vulnerability.
• Privileges Required (PR): None (N) - The malicious app does not require elevated privileges to run.
• User Interaction (UI): Required (R) - The user must execute the malicious app.
• Scope (S): Unchanged (U) - The vulnerability does not allow the attacker to affect resources beyond the app's sandbox.
• Confidentiality (C): High (H) - The vulnerability allows access to private information.
• Integrity (I): None (N) - The vulnerability does not allow modification of data.
• Availability (A): None (N) - The vulnerability does not affect system availability.

Estimated CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Estimated Base Score: 5.5 (Medium)

Threat Level: Medium. The vulnerability requires user interaction and local access, but the potential for data exfiltration is significant.

Deep Dive & Mechanics

The vulnerability lies in the macOS security framework, specifically in how the operating system enforces privacy permissions for applications. macOS uses a system of entitlements and sandbox profiles to restrict what an app can access (e.g., contacts, location, files). CVE-2025-30431 indicates that a malicious app can bypass these checks and access private information without proper authorization.

The exact mechanism is not publicly disclosed, but it likely involves one of the following:

1. Entitlement Bypass: The app may be able to request and receive entitlements it should not have, or it may be able to use a system service that does not properly validate the caller's entitlements.
2. Sandbox Escape: The app may be able to escape its sandbox and access resources outside its designated container.
3. Inter-Process Communication (IPC) Abuse: The app may be able to communicate with a privileged process (e.g., a system daemon) and trick it into providing access to private data.
4. TCC (Transparency, Consent, and Control) Bypass: The app may be able to access protected resources (like the camera, microphone, or files) without triggering the TCC prompt or by bypassing the user's consent.

The patch "addressed with improved checks" suggests that Apple has strengthened the validation logic in one or more of these areas.

Vulnerable vs. Patched Code

Since no specific code or patch diff is publicly available, we can only describe the general nature of the fix.

Vulnerable Code (Conceptual):

// Hypothetical vulnerable function in a system daemon
bool check_access(pid_t caller_pid, resource_t resource) {
    // Insufficient check: only verifies the caller is a valid process
    if (is_valid_process(caller_pid)) {
        return true; // Grant access
    }
    return false;
}

Patched Code (Conceptual):

// Hypothetical patched function
bool check_access(pid_t caller_pid, resource_t resource) {
    // Improved check: verifies the caller has the required entitlement
    if (is_valid_process(caller_pid) && has_entitlement(caller_pid, resource)) {
        return true; // Grant access
    }
    return false;
}

The patched code now includes an additional check to ensure the calling process has the specific entitlement required to access the resource.

Exploitation & Lab Setup

No public exploit code is available for CVE-2025-30431. The following is a hypothetical lab setup and exploitation scenario for educational purposes.

Red Team (Exploitation)

Lab Setup:

1. Target: macOS Ventura 13.7.4 (unpatched) running in a virtual machine (e.g., using VMware Fusion or Parallels).
2. Attacker Machine: Kali Linux or any system with a C2 framework.
3. Malicious App: A signed or unsigned macOS application bundle (.app) that contains the exploit code.

Exploitation Steps:

1. Develop the Malicious App: Create a macOS app that, when executed, attempts to access a protected resource (e.g., the user's address book or keychain) without proper authorization.
2. Bypass Security Checks: The app would use the specific technique (e.g., entitlement bypass, IPC abuse) to circumvent the privacy controls.
3. Exfiltrate Data: Once access is gained, the app would read the private data and send it to an attacker-controlled server.
4. Deliver the App: The attacker would use social engineering (e.g., phishing email with a malicious attachment) to trick the user into running the app.

Hypothetical Exploit Code (Python-like pseudocode):

import objc
from Foundation import NSBundle

# Attempt to access the user's address book without permission
def exploit_address_book():
    # This would fail on a patched system
    address_book = NSBundle.bundleWithIdentifier_("com.apple.AddressBook")
    if address_book:
        # Access private data
        people = address_book.classNamed_("ABAddressBook").sharedAddressBook().people()
        for person in people:
            print(person.valueForProperty_("First"))

Blue Team (Detection & Response)

Detection Steps:

1. Monitor for Suspicious App Execution: Use endpoint detection and response (EDR) tools to monitor for the execution of unsigned or untrusted applications, especially those that attempt to access protected resources.
2. Analyze App Behavior: Look for applications that make unusual system calls or attempt to access resources without the proper entitlements.
3. Check for TCC Bypass Attempts: Monitor TCC database (/Library/Application Support/com.apple.TCC/TCC.db) for unauthorized access attempts.
4. Review System Logs: Use the log command to review system logs for privacy-related events.

Response Steps:

1. Isolate the System: Disconnect the affected system from the network.
2. Identify the Malicious App: Locate and quarantine the malicious application.
3. Collect Forensic Evidence: Capture memory, disk, and network artifacts for analysis.
4. Apply Patches: Ensure the system is updated to the latest patched version of macOS.

Indicators of Compromise (IOCs)

No specific IOCs are available for this CVE. The following are general indicators of a potential exploitation attempt:

• File Indicators:
  • Unsigned or ad-hoc signed .app bundles in unusual locations (e.g., /tmp, ~/Downloads).
  • Mach-O binaries with suspicious entitlements (e.g., com.apple.security.cs.disable-library-validation).
• Network Indicators:
  • Outbound connections to unknown IP addresses or domains from a non-browser application.
  • DNS queries for suspicious domains.
• Behavioral Indicators:
  • An application attempting to access the address book, calendar, or location services without a prompt.
  • An application making unexpected system calls to task_for_pid, mach_vm_remap, or other privileged APIs.
  • Unusual entries in the TCC database.

Detection Engineering

YARA Rule

rule CVE_2025_30431_Malicious_App {
    meta:
        description = "Detects potential malicious macOS apps exploiting CVE-2025-30431"
        author = "Valters IT"
        date = "2025-04-10"
        hash = "unknown"
    strings:
        $s1 = "ABAddressBook" nocase
        $s2 = "sharedAddressBook" nocase
        $s3 = "valueForProperty_" nocase
        $s4 = "com.apple.security.cs.disable-library-validation" nocase
        $s5 = "task_for_pid" nocase
    condition:
        (uint16(0) == 0xcefa or uint16(0) == 0xfeed) and // Mach-O magic
        (any of ($s*))
}

Sigma Rule

title: Suspicious macOS App Accessing Private Data
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects a macOS application attempting to access private data without proper entitlements.
author: Valters IT
date: 2025/04/10
tags:
    - attack.t1204
    - cve.2025.30431
logsource:
    product: macos
    category: process_creation
detection:
    selection:
        Image|endswith: '.app/Contents/MacOS/'
        CommandLine|contains:
            - 'ABAddressBook'
            - 'sharedAddressBook'
            - 'valueForProperty_'
            - 'task_for_pid'
    condition: selection
falsepositives:
    - Legitimate applications that use these APIs with proper entitlements.
level: high

Suricata Rule

alert ip any any -> any any (msg:"CVE-2025-30431 - Potential macOS Data Exfiltration"; content:"|7b 22 64 61 74 61 22 3a|"; sid:1000001; rev:1;)

Note: The Suricata rule above is a generic example for detecting JSON data exfiltration. A more specific rule would require knowledge of the actual exfiltration method.

Remediation & Mitigation

Immediate Remediation:

1. Apply Patches: Update all affected macOS systems to the latest patched versions:
   • macOS Sequoia 15.4 or later
   • macOS Sonoma 14.7.5 or later
   • macOS Ventura 13.7.5 or later
2. Verify Patch Status: Use the softwareupdate command or System Settings to confirm the update is installed.

Mitigation Steps (if patching is not immediately possible):

1. Restrict App Execution: Use macOS's built-in Gatekeeper and Notarization features to only allow trusted apps to run.
2. Enable Firewall: Turn on the macOS firewall to block unauthorized outbound connections.
3. Monitor TCC Database: Regularly audit the TCC database for unauthorized access grants.
4. User Education: Train users to avoid running untrusted applications and to be cautious of phishing attempts.
5. Use EDR Solutions: Deploy endpoint detection and response (EDR) solutions that can monitor for suspicious behavior.

Long-Term Recommendations:

1. Adopt a Zero Trust Model: Assume that any application could be malicious and enforce least-privilege access.
2. Regular Security Audits: Conduct regular security audits of macOS systems and applications.
3. Stay Informed: Monitor Apple security updates and CVE databases for new vulnerabilities.

Valters IT
DevSecOps & Cyber Threat Intelligence