CVE-2025-43215: Apple macOS Information Disclosure Flaw

CVE-2025-43215 Overview

CVE-2025-43215 is an information disclosure vulnerability in Apple macOS image processing. Processing a maliciously crafted image can result in disclosure of process memory. Apple addressed the issue with improved checks in macOS Sequoia 15.6. The flaw is categorized under [CWE-200] Exposure of Sensitive Information to an Unauthorized Actor.

Exploitation requires local access and user interaction, such as opening a crafted image file. Successful exploitation leaks in-process memory contents, which may contain sensitive data including cryptographic material, tokens, or pointers useful for bypassing address space layout randomization (ASLR).

Critical Impact
A crafted image opened on an unpatched macOS system can leak process memory to a local attacker, enabling further exploitation or credential theft.

Affected Products

Apple macOS versions prior to Sequoia 15.6
Applications on macOS that process images via affected system frameworks
Systems where users open untrusted image files from email, web, or messaging clients

Discovery Timeline

2025-07-30 - CVE-2025-43215 published to the National Vulnerability Database (NVD)
2025-07-30 - Apple releases macOS Sequoia 15.6 with the fix (Apple Support Advisory)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-43215

Vulnerability Analysis

The vulnerability resides in macOS image parsing routines that fail to properly validate data within maliciously crafted image files. When the affected code processes such an image, it reads beyond the intended buffer boundaries or uses uninitialized memory, returning process memory contents to the caller. This behavior aligns with an out-of-bounds read information disclosure pattern.

Apple's advisory states the issue was addressed with improved checks, indicating the fix adds validation on image metadata or pixel data before memory access. The vulnerability does not permit code execution or data modification on its own. However, disclosed memory contents can defeat ASLR and expose secrets that assist chained exploitation.

Root Cause

The root cause is insufficient bounds or state validation in the macOS image decoder when parsing crafted input. Missing checks allow the decoder to read memory outside the intended image buffer or return uninitialized bytes to the requesting process. See the Apple Support Advisory for macOS Sequoia 15.6 for vendor details.

Attack Vector

An attacker delivers a specially crafted image to a target user through email, messaging, a website, or shared storage. When a macOS application processes the image using the affected framework, the decoder leaks memory into the application's output or into an accessible buffer. Additional technical context is available in the Full Disclosure mailing list post.

No public proof-of-concept exploit is listed in the NVD data, and the vulnerability is not present in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2025-43215

Indicators of Compromise

Unexpected image files delivered from untrusted sources, particularly with malformed headers or nonstandard metadata
macOS endpoints running Sequoia versions earlier than 15.6
Application crashes or memory sanitizer alerts triggered when opening image files in Preview, Safari, Mail, or Messages

Detection Strategies

Inventory macOS endpoints to identify hosts running versions earlier than macOS Sequoia 15.6
Monitor endpoint telemetry for image-parsing processes reading anomalous file formats or crashing during decode
Correlate delivery of image attachments with subsequent process anomalies on the receiving endpoint

Monitoring Recommendations

Ingest macOS unified log and endpoint process telemetry into a centralized analytics platform for cross-host correlation
Alert on ImageIO or related framework crashes observed shortly after inbound file delivery
Track patch compliance for macOS Sequoia 15.6 across the fleet and flag lagging hosts

How to Mitigate CVE-2025-43215

Immediate Actions Required

Upgrade all macOS endpoints to macOS Sequoia 15.6 or later
Prioritize patching for developer, executive, and high-value user endpoints handling sensitive documents
Advise users to avoid opening image files from untrusted sources until patches are applied

Patch Information

Apple fixed CVE-2025-43215 in macOS Sequoia 15.6 by adding improved checks in the affected image processing code path. Refer to the Apple Support Advisory for the full list of addressed issues and installation guidance. Deploy the update through Apple Software Update, an MDM solution, or managed patching tooling.

Workarounds

Restrict image previews in email and messaging clients where feasible
Use application allowlisting or attachment filtering at the mail gateway to block suspicious image formats
Educate users on the risk of opening unsolicited image attachments

bash

# Verify macOS version and apply available updates
sw_vers -productVersion
sudo softwareupdate --install --all --restart