CVE-2025-43219: macOS Sequoia Buffer Overflow Vulnerability

CVE-2025-43219 Overview

CVE-2025-43219 is a memory corruption vulnerability affecting macOS Sequoia that can be triggered through processing maliciously crafted image files. The vulnerability stems from improper memory handling in the image processing components of the operating system, which could allow an attacker to corrupt process memory when a victim opens or previews a specially crafted image.

Critical Impact

Processing a maliciously crafted image file may lead to process memory corruption, potentially enabling arbitrary code execution with the privileges of the affected application.

Affected Products

• macOS Sequoia versions prior to 15.6

Discovery Timeline

• 2026-04-02 - CVE-2025-43219 published to NVD
• 2026-04-02 - Last updated in NVD database

Technical Details for CVE-2025-43219

Vulnerability Analysis

This vulnerability exists in the image processing subsystem of macOS Sequoia. When the operating system attempts to parse and render a maliciously crafted image file, improper memory handling can lead to memory corruption within the processing application. The vulnerability requires user interaction—specifically, the victim must open or preview a malicious image file—but can be delivered through various vectors including email attachments, web downloads, or shared files.

The network attack vector indicates that the malicious image can be delivered remotely, while the requirement for user interaction means an attacker must entice a user to open the crafted file. Successful exploitation could result in complete compromise of confidentiality, integrity, and availability of the affected process.

Root Cause

The root cause of this vulnerability lies in improper memory handling within macOS's image processing routines. When processing certain image file formats, the system fails to properly validate or manage memory operations, leading to a condition where memory corruption can occur. Apple addressed this issue by implementing improved memory handling to ensure proper bounds checking and memory management during image processing operations.

Attack Vector

The attack vector for CVE-2025-43219 involves delivering a specially crafted image file to a target user. Potential delivery methods include:

• Email attachments containing malicious images
• Malicious websites hosting crafted image files
• Shared files through messaging applications or file sharing services
• Malicious image files in downloaded archives or documents

When the victim's macOS system processes the malicious image (through Preview, Finder thumbnails, Quick Look, or other image-rendering applications), the memory corruption can be triggered. The vulnerability does not require elevated privileges to exploit, making it accessible to any attacker who can deliver the malicious content to a user.

Detection Methods for CVE-2025-43219

Indicators of Compromise

• Unexpected application crashes when opening or previewing image files
• Anomalous memory access patterns in image processing applications like Preview, Photos, or Quick Look
• Crash reports indicating memory corruption in image codec libraries

Detection Strategies

• Monitor for abnormal crash reports in image processing applications with memory corruption signatures
• Implement endpoint detection rules for unusual child process spawning from image viewer applications
• Deploy file scanning solutions capable of detecting malformed image file structures

Monitoring Recommendations

• Enable crash reporting collection to identify potential exploitation attempts across endpoints
• Monitor for suspicious image file downloads or attachments with unusual file characteristics
• Review system logs for repeated crashes in image processing services or applications

How to Mitigate CVE-2025-43219

Immediate Actions Required

• Update macOS Sequoia to version 15.6 or later immediately
• Exercise caution when opening image files from untrusted or unknown sources
• Consider disabling automatic image preview features until patches are applied
• Implement email filtering to scan attachments for potentially malicious image files

Patch Information

Apple has addressed this vulnerability in macOS Sequoia 15.6 by implementing improved memory handling in the affected image processing components. Users should update to this version or later through System Settings > General > Software Update, or by downloading the update directly from Apple. For detailed information about the security content of this update, refer to the Apple Security Advisory.

Workarounds

• Avoid opening image files from untrusted sources until the patch is applied
• Use alternative image viewing applications that do not rely on the affected system components
• Implement network-level filtering to block potentially malicious image files
• Consider using sandboxed environments when viewing images from unknown sources