CVE-2025-43386: Apple iPadOS Buffer Overflow Vulnerability

CVE-2025-43386 Overview

CVE-2025-43386 is an out-of-bounds access vulnerability affecting multiple Apple operating systems. The flaw resides in media file processing components shared across iOS, iPadOS, macOS, tvOS, and visionOS. Processing a maliciously crafted media file may lead to unexpected app termination or corrupt process memory. Apple addressed the issue with improved bounds checking in iOS 18.7.2, iPadOS 18.7.2, iOS 26.1, iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, and visionOS 26.1. The vulnerability is categorized as [CWE-125] Out-of-Bounds Read. Local exploitation requires user interaction, typically by opening or previewing the crafted media content.

Critical Impact
Processing a maliciously crafted media file may corrupt process memory and cause unexpected application termination on affected Apple devices.

Affected Products

Apple iOS and iPadOS (versions prior to 18.7.2 and 26.1)
Apple macOS Tahoe (versions prior to 26.1) and Apple tvOS (versions prior to 26.1)
Apple visionOS (versions prior to 26.1)

Discovery Timeline

2025-11-04 - CVE-2025-43386 published to NVD
2026-04-02 - Last updated in NVD database

Technical Details for CVE-2025-43386

Vulnerability Analysis

The vulnerability is an out-of-bounds access flaw in Apple's media file parsing logic. When the affected component processes a media file with malformed structural fields, it reads or accesses memory locations outside the bounds of the allocated buffer. This memory corruption can terminate the application or alter the state of adjacent process memory. The flaw is tracked as [CWE-125] Out-of-Bounds Read, indicating insufficient validation of length or offset values during parsing. Exploitation requires the victim to open or process the crafted media file locally, satisfying the user interaction requirement.

Root Cause

The root cause is insufficient bounds checking when parsing fields within a media file. Length, offset, or index values supplied by the file are used to access buffer memory without validation against allocation size. Apple's fix introduces improved bounds checking to reject or constrain values that would otherwise produce out-of-bounds accesses.

Attack Vector

An attacker delivers a crafted media file through email, messaging, web download, or shared storage. When the victim opens the file in an affected Apple application, the parser triggers the out-of-bounds access. The resulting memory corruption may crash the application or destabilize the process. Apple's advisory does not confirm arbitrary code execution, but corrupted process memory can be a precursor to further exploitation chains.

No verified public proof-of-concept code is available. Refer to the Apple Security Advisory #125632 and related advisories for component-level details.

Detection Methods for CVE-2025-43386

Indicators of Compromise

Unexpected crashes or terminations of media-handling applications coinciding with the receipt or opening of untrusted media files.
Crash reports in ~/Library/Logs/DiagnosticReports/ referencing out-of-bounds access or memory corruption in media parsing libraries.
Receipt of media files from untrusted senders via Mail, Messages, or AirDrop immediately preceding application instability.

Detection Strategies

Monitor endpoint telemetry for repeated application crashes on Apple devices, particularly those tied to media processing components.
Correlate file delivery events (email attachments, messaging payloads) with subsequent process termination events.
Inspect inbound media files at the mail or web gateway using format validation tools to flag structurally anomalous files.

Monitoring Recommendations

Aggregate Apple device crash logs to a central log platform and alert on clusters of media-related faults.
Track OS version compliance to identify devices still running pre-18.7.2 or pre-26.1 builds.
Review mobile device management (MDM) inventory reports to confirm timely deployment of Apple security updates.

How to Mitigate CVE-2025-43386

Immediate Actions Required

Update affected devices to iOS 18.7.2, iPadOS 18.7.2, iOS 26.1, iPadOS 26.1, macOS Tahoe 26.1, tvOS 26.1, or visionOS 26.1.
Enforce automatic updates via MDM policy for managed Apple endpoints to close the exposure window.
Instruct users to avoid opening media files received from untrusted sources until patches are applied.

Patch Information

Apple has released patches addressing CVE-2025-43386 across affected platforms. Consult the Apple Security Advisory #125632, Apple Security Advisory #125633, Apple Security Advisory #125634, Apple Security Advisory #125637, and Apple Security Advisory #125638 for platform-specific fixed build numbers.

Workarounds

No vendor-supplied workaround exists; applying the security update is the only supported remediation.
Restrict opening media attachments from unknown senders and disable automatic media previews where feasible.
Use MDM configuration profiles to enforce attachment handling restrictions on managed devices.

bash

# Verify installed iOS/iPadOS version meets the patched baseline
# On a managed device, retrieve OS version via MDM query or:
softwareversion=$(sw_vers -productVersion)
echo "Current OS version: $softwareversion"
# Compare against 18.7.2 or 26.1 minimum