CVE-2025-43238: macOS Integer Overflow DoS Vulnerability

CVE-2025-43238 Overview

CVE-2025-43238 is an integer overflow vulnerability affecting multiple versions of macOS. The vulnerability exists due to insufficient input validation when processing certain data, allowing a malicious application to trigger an integer overflow condition. When exploited, this can lead to unexpected system termination, causing a denial of service condition on affected systems.

Critical Impact

A malicious application can cause unexpected system termination, potentially disrupting user workflows and system availability on macOS devices.

Affected Products

• macOS Sequoia versions prior to 15.6
• macOS Sonoma versions prior to 14.7.7
• macOS Ventura versions prior to 13.7.7

Discovery Timeline

• 2026-04-02 - CVE-2025-43238 published to NVD
• 2026-04-02 - Last updated in NVD database

Technical Details for CVE-2025-43238

Vulnerability Analysis

This vulnerability is classified as an Integer Overflow (CWE-190), a type of memory corruption flaw that occurs when an arithmetic operation produces a value that exceeds the maximum size of the integer type used to store it. In this case, the overflow condition can be triggered locally by a malicious application without requiring any user interaction or special privileges.

The vulnerability requires local access to exploit, meaning an attacker would need to execute malicious code on the target system. This could be achieved through social engineering tactics to convince users to install a malicious application, or by leveraging an existing foothold on the system.

Root Cause

The root cause of CVE-2025-43238 stems from improper input validation in macOS system components. When processing certain input values, the system fails to adequately verify that arithmetic operations will not exceed the bounds of the integer data type being used. This oversight allows specially crafted input to trigger an integer overflow condition.

Integer overflow vulnerabilities occur when the result of an arithmetic operation exceeds the storage capacity of the variable type. In languages like C and C++, which are commonly used in operating system development, integer overflows can lead to unexpected behavior including memory corruption, incorrect calculations, and in this case, system instability.

Attack Vector

The attack vector for this vulnerability is local, requiring an attacker to have the ability to execute code on the target macOS system. The exploitation scenario involves:

1. An attacker creates a malicious application designed to trigger the integer overflow condition
2. The victim installs or executes the malicious application on their macOS system
3. The application provides specially crafted input that causes the integer overflow
4. The overflow condition leads to unexpected system termination

The vulnerability does not require any specific privileges to exploit, and no user interaction is needed beyond running the malicious application. The impact is limited to availability (denial of service) rather than confidentiality or integrity compromise.

The integer overflow vulnerability manifests during input processing operations within macOS system components. When a malicious application provides values that cause arithmetic operations to exceed integer bounds, the system fails to handle the overflow condition gracefully, resulting in system termination. For detailed technical information, refer to Apple Security Advisory 124149.

Detection Methods for CVE-2025-43238

Indicators of Compromise

• Unexpected system crashes or kernel panics on macOS systems without apparent cause
• Repeated system terminations occurring after running specific applications
• System logs showing abnormal termination events correlated with application execution
• Crash reports indicating memory-related issues in system components

Detection Strategies

• Monitor macOS system logs for unexpected termination events and kernel panic reports
• Deploy endpoint detection solutions capable of identifying applications exhibiting suspicious behavior patterns
• Implement application whitelisting to prevent execution of unauthorized applications
• Review crash reports for patterns indicating potential exploitation attempts

Monitoring Recommendations

• Enable comprehensive system logging on macOS endpoints to capture termination events
• Configure centralized log collection to correlate crash events across multiple systems
• Set up alerts for unusual patterns of system instability or repeated crashes
• Monitor application installation activity for potentially malicious software

How to Mitigate CVE-2025-43238

Immediate Actions Required

• Update macOS Sequoia to version 15.6 or later immediately
• Update macOS Sonoma to version 14.7.7 or later immediately
• Update macOS Ventura to version 13.7.7 or later immediately
• Review recently installed applications and remove any untrusted software

Patch Information

Apple has addressed this vulnerability with improved input validation in the following macOS versions:

• macOS Sequoia 15.6 - See Apple Security Advisory 124149
• macOS Sonoma 14.7.7 - See Apple Security Advisory 124150
• macOS Ventura 13.7.7 - See Apple Security Advisory 124151

Organizations should prioritize applying these updates to all affected macOS systems. The patches implement improved input validation to prevent the integer overflow condition from being triggered.

Workarounds

• Restrict application installations to only trusted sources (Mac App Store or identified developers)
• Enable Gatekeeper to prevent execution of unsigned or untrusted applications
• Implement endpoint protection solutions that can detect and block malicious application behavior
• Educate users about the risks of installing applications from unknown sources

# Verify Gatekeeper is enabled
spctl --status

# Enable Gatekeeper if disabled
sudo spctl --master-enable

# Check current macOS version
sw_vers -productVersion

# List pending software updates
softwareupdate --list