CVE-2025-43373: Apple macOS Buffer Overflow Vulnerability

CVE-2025-43373 Overview

CVE-2025-43373 is a memory corruption vulnerability affecting Apple macOS. A malicious application can trigger unexpected system termination or corrupt kernel memory due to improper memory handling. Apple addressed the issue with improved memory handling in macOS Sequoia 15.7.2, macOS Sonoma 14.8.2, and macOS Tahoe 26.1.

The weakness is classified under [CWE-119], improper restriction of operations within the bounds of a memory buffer. The vulnerability impacts the kernel surface and can be reached by an application running on the affected system.

Critical Impact

An app can cause unexpected system termination or corrupt kernel memory on unpatched macOS versions.

Affected Products

• Apple macOS Sequoia prior to 15.7.2
• Apple macOS Sonoma prior to 14.8.2
• Apple macOS Tahoe prior to 26.1

Discovery Timeline

• 2025-11-04 - CVE-2025-43373 published to NVD
• 2026-04-02 - Last updated in NVD database

Technical Details for CVE-2025-43373

Vulnerability Analysis

The vulnerability is a memory corruption issue in macOS that affects kernel memory integrity. Apple's advisory states the flaw was addressed with improved memory handling, indicating that the original code did not correctly enforce buffer or object lifetime boundaries during a kernel-reachable operation. Triggering the condition allows an application to either crash the system or corrupt kernel memory structures.

The CWE classification of [CWE-119] places this issue in the class of memory safety errors involving improper buffer bounds enforcement. Kernel memory corruption flaws of this type often serve as primitives in broader exploit chains targeting privilege escalation or kernel code execution.

Root Cause

The root cause is improper memory handling within a macOS component reachable from user-mode applications. Apple has not published low-level details of the affected code path. The patched releases introduce stricter validation and lifecycle management to prevent out-of-bounds access or corruption of kernel objects.

Attack Vector

Exploitation requires running a malicious application on the target macOS host. While the CVSS vector lists a network attack vector, the practical trigger described by Apple is an application on the system invoking the vulnerable code path. A successful attempt results in kernel memory corruption or a system panic.

No public proof-of-concept code or exploit is available for CVE-2025-43373. The vulnerability mechanism is described in prose only; refer to the Apple Support Article 125634 for vendor details.

Detection Methods for CVE-2025-43373

Indicators of Compromise

• Unexpected kernel panics or system reboots on macOS hosts running versions earlier than 15.7.2, 14.8.2, or 26.1.
• Crash reports referencing kernel memory faults, page faults, or invalid memory access in /Library/Logs/DiagnosticReports/.
• Installation or execution of untrusted applications shortly before kernel instability events.

Detection Strategies

• Inventory macOS endpoints and flag any host below the patched build numbers as exposed.
• Correlate kernel panic logs with recently launched processes to identify suspicious applications.
• Monitor for repeated abnormal terminations across managed Mac fleets, which can indicate exploitation attempts.

Monitoring Recommendations

• Centralize macOS unified logs and DiagnosticReports for security analytics.
• Alert on unsigned or newly observed binaries that precede kernel-level crash events.
• Track patch deployment status against Apple Support Article 125635 and Apple Support Article 125636.

How to Mitigate CVE-2025-43373

Immediate Actions Required

• Update affected hosts to macOS Sequoia 15.7.2, macOS Sonoma 14.8.2, or macOS Tahoe 26.1.
• Restrict installation of untrusted third-party applications until patching is complete.
• Verify Gatekeeper and System Integrity Protection are enabled across the fleet.

Patch Information

Apple released fixes in macOS Sequoia 15.7.2, macOS Sonoma 14.8.2, and macOS Tahoe 26.1. Patch details are documented in Apple Support Article 125634, Apple Support Article 125635, and Apple Support Article 125636. Apply updates through Software Update or an MDM solution.

Workarounds

• No vendor-supplied workaround exists; patching is the only supported remediation.
• Limit local application execution to vetted, signed software to reduce exposure.
• Enforce least-privilege user accounts to constrain the impact of malicious applications.

# Verify the installed macOS version meets the patched build
sw_vers -productVersion

# Trigger software update check
sudo softwareupdate -l
sudo softwareupdate -ia --restart