CVE-2025-43186: Apple iPadOS Buffer Overflow Vulnerability

CVE-2025-43186 Overview

CVE-2025-43186 is a memory handling vulnerability affecting multiple Apple operating systems that can be triggered when parsing a maliciously crafted file. The vulnerability stems from improper memory handling (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer), which can lead to unexpected application termination. Apple has addressed this issue with improved memory handling across all affected platforms.

Critical Impact

This vulnerability allows remote attackers to potentially crash applications or cause denial of service conditions through network-delivered malicious files without requiring user authentication or privileges.

Affected Products

• Apple iOS (prior to 18.6)
• Apple iPadOS (prior to 18.6)
• Apple macOS Sequoia (prior to 15.6)
• Apple macOS Sonoma (prior to 14.7.7)
• Apple macOS Ventura (prior to 13.7.7)
• Apple tvOS (prior to 18.6)
• Apple visionOS (prior to 2.6)
• Apple watchOS (prior to 11.6)

Discovery Timeline

• July 30, 2025 - CVE-2025-43186 published to NVD
• November 03, 2025 - Last updated in NVD database

Technical Details for CVE-2025-43186

Vulnerability Analysis

This vulnerability is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), indicating a memory corruption issue within Apple's file parsing mechanisms. When a specially crafted file is processed by an affected application, the system fails to properly handle memory operations, resulting in a buffer boundary violation. This can cause the application to terminate unexpectedly, effectively creating a denial of service condition.

The vulnerability is particularly concerning because it can be exploited remotely through network-delivered files without requiring any user credentials or elevated privileges. The attack complexity is low, meaning that exploitation does not require sophisticated techniques or specialized access conditions.

Root Cause

The root cause of CVE-2025-43186 lies in inadequate bounds checking during file parsing operations. When processing certain file structures, the affected Apple system components fail to properly validate memory boundaries, allowing operations to exceed allocated buffer limits. This improper memory handling can corrupt adjacent memory regions, leading to application instability and crashes.

Apple's fix involves implementing improved memory handling routines that enforce proper boundary validation during file parsing operations, ensuring that memory operations remain within allocated buffer constraints.

Attack Vector

The attack vector for this vulnerability is network-based, allowing remote exploitation without user interaction in the worst-case scenario. An attacker could deliver a maliciously crafted file through various channels:

• Email attachments that are automatically parsed
• Malicious content delivered through web browsing
• Files shared through messaging applications
• Documents received through AirDrop or similar file sharing mechanisms

When the vulnerable application parses the malicious file, the memory corruption triggers, causing the application to crash. While the primary impact described is application termination (denial of service), memory corruption vulnerabilities of this class can potentially be leveraged for more severe attacks if proper memory protections are not in place.

Detection Methods for CVE-2025-43186

Indicators of Compromise

• Unexpected application crashes occurring during file parsing or opening operations
• System logs showing memory access violations or segmentation faults in file handling components
• Repeated crash reports related to document or media file processing
• Abnormal memory consumption patterns prior to application termination

Detection Strategies

• Monitor system crash logs (/var/log/DiagnosticMessages/ on macOS) for patterns indicating memory corruption during file operations
• Implement endpoint detection rules to identify unusual file parsing behavior followed by process termination
• Deploy SentinelOne agents to detect and alert on memory corruption exploitation attempts in real-time
• Review Apple Crash Reporter data for recurring crashes with similar stack traces pointing to file parsing functions

Monitoring Recommendations

• Enable enhanced logging for file operations across Apple devices managed in your environment
• Configure MDM solutions to monitor and report application crashes on iOS, iPadOS, and macOS devices
• Establish baseline behavior for critical applications to identify anomalous crash patterns
• Implement network monitoring to detect delivery of potentially malicious files targeting this vulnerability

How to Mitigate CVE-2025-43186

Immediate Actions Required

• Update all Apple devices to the latest patched versions: iOS 18.6, iPadOS 18.6, macOS Sequoia 15.6, macOS Sonoma 14.7.7, macOS Ventura 13.7.7, tvOS 18.6, visionOS 2.6, and watchOS 11.6
• Prioritize patching for devices that handle untrusted files or are exposed to network-delivered content
• Review organizational MDM policies to ensure automatic security updates are enabled
• Temporarily restrict handling of files from untrusted sources on unpatched devices

Patch Information

Apple has released security updates addressing this vulnerability across all affected platforms. Organizations should apply these patches immediately:

• iOS and iPadOS 18.6: Apple Security Update 124147
• macOS Sequoia 15.6: Apple Security Update 124149
• macOS Sonoma 14.7.7: Apple Security Update 124150
• macOS Ventura 13.7.7: Apple Security Update 124151
• tvOS 18.6: Apple Security Update 124153
• visionOS 2.6: Apple Security Update 124154
• watchOS 11.6: Apple Security Update 124155

Additional technical details are available through the Full Disclosure security list.

Workarounds

• Implement network-level filtering to block known malicious file types until patches can be applied
• Configure email and web gateway security controls to scan and quarantine suspicious file attachments
• Use application sandboxing where available to limit the impact of potential exploitation
• Enable Gatekeeper and other macOS security features to restrict execution of untrusted content

# Verify current macOS version
sw_vers -productVersion

# Check for available updates on macOS
softwareupdate --list

# Install all available security updates
softwareupdate --install --all

# For iOS/iPadOS devices, verify version via Settings > General > About
# Update via Settings > General > Software Update