CVE-2026-64766: Apple iPadOS RCE Vulnerability

CVE-2026-64766 Overview

CVE-2026-64766 is an integer overflow vulnerability [CWE-190] affecting multiple Apple operating systems. Processing a maliciously crafted file may lead to unexpected app termination or arbitrary code execution on affected devices. Apple addressed the issue with improved input validation across its product line.

The flaw requires local access and user interaction, but successful exploitation yields high impact to confidentiality, integrity, and availability. Attackers can weaponize the vulnerability by delivering a crafted file to a victim through email, messaging, or web downloads.

Critical Impact
Processing a maliciously crafted file may lead to unexpected app termination or arbitrary code execution across iOS, iPadOS, macOS, tvOS, visionOS, and watchOS.

Affected Products

Apple iOS and iPadOS prior to 26.6
Apple macOS Sequoia prior to 15.7.8, macOS Sonoma prior to 14.8.8, and macOS Tahoe prior to 26.6
Apple tvOS, visionOS, and watchOS prior to 26.6

Discovery Timeline

2026-07-27 - CVE-2026-64766 published to NVD
2026-07-29 - Last updated in NVD database

Technical Details for CVE-2026-64766

Vulnerability Analysis

CVE-2026-64766 is classified as an integer overflow weakness [CWE-190] in file-processing code shared across Apple operating systems. When affected code parses a maliciously crafted file, arithmetic operations on untrusted size or index fields exceed the maximum representable value of the underlying integer type. The resulting wraparound produces incorrect buffer allocations or bounds calculations.

Downstream memory operations then read or write outside intended boundaries. This corrupts adjacent memory structures and can hand control-flow to attacker-supplied data. Apple's advisory confirms outcomes ranging from unexpected app termination to arbitrary code execution within the context of the parsing process.

Because the vulnerable code path exists across iOS, iPadOS, macOS, tvOS, visionOS, and watchOS, the vulnerability spans Apple's entire consumer and enterprise device fleet. Apple resolved the issue with improved input validation on the affected size and index calculations.

Root Cause

The root cause is missing or insufficient validation of numeric fields parsed from a file before those values are used in memory arithmetic. Attacker-controlled values trigger an integer overflow, breaking the invariants that later memory operations rely on for safety.

Attack Vector

Exploitation requires a local attack vector with user interaction. A victim must open or process a crafted file delivered through email attachments, messaging apps, web downloads, or shared storage. No prior privileges are required on the target system, and successful exploitation can execute code in the affected application's context.

No public proof-of-concept exploit is available, and CISA has not listed the CVE in the Known Exploited Vulnerabilities catalog. See the Apple Security Update Advisory for vendor technical details.

Detection Methods for CVE-2026-64766

Indicators of Compromise

Unexpected termination or repeated crash reports from file-parsing applications on Apple endpoints
Crash logs referencing memory corruption, EXC_BAD_ACCESS, or heap overflow signatures following the opening of an untrusted file
Delivery of unusual or malformed file attachments through email, messaging, or web download channels immediately before application crashes

Detection Strategies

Monitor macOS and iOS crash reporter output for repeated faults in file-handling frameworks and correlate with recent file downloads
Inspect endpoint telemetry for child processes or shell activity spawned by user applications shortly after file open events
Compare installed OS build versions against Apple's fixed releases to identify unpatched devices in the fleet

Monitoring Recommendations

Ingest macOS unified logs and iOS mobile device management (MDM) telemetry into a central analytics platform for correlation
Alert on any process crashes followed by unexpected network connections or persistence artifacts on the same host
Track email and web gateway logs for delivery of file types associated with the vulnerable parsers

How to Mitigate CVE-2026-64766

Immediate Actions Required

Update all Apple devices to iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, or watchOS 26.6
Inventory devices through MDM to identify systems still running vulnerable builds and prioritize remediation
Warn users against opening unsolicited files from untrusted sources until patches are deployed

Patch Information

Apple has released fixes across its platforms. Refer to the vendor advisories for build numbers and download instructions: iOS and iPadOS, macOS Sequoia, macOS Sonoma, macOS Tahoe, tvOS, visionOS, and watchOS.

Workarounds

Restrict opening of untrusted files on unpatched devices, particularly file types processed by system frameworks
Enforce MDM policies that block sideloaded content and require automatic OS updates on managed endpoints
Use email and web filtering to strip or sandbox attachments from untrusted senders until patching completes

bash

# Verify current macOS build against the fixed release
sw_vers -productVersion
softwareupdate --list
sudo softwareupdate --install --all --restart