CVE-2026-64774 Overview
CVE-2026-64774 is an integer overflow vulnerability [CWE-190] affecting multiple Apple operating systems. Apple addressed the flaw with improved input validation across iOS, iPadOS, macOS, tvOS, and visionOS. A remote attacker can trigger the condition over the network without authentication or user interaction. Successful exploitation causes unexpected application termination or heap corruption, which can lead to arbitrary code execution. Apple published fixes in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, and visionOS 26.6.
Critical Impact
Remote, unauthenticated attackers can trigger heap corruption on unpatched Apple devices, creating a path to arbitrary code execution and full device compromise.
Affected Products
- Apple iOS and iPadOS versions prior to 26.6
- Apple macOS Sequoia prior to 15.7.8, macOS Sonoma prior to 14.8.8, macOS Tahoe prior to 26.6
- Apple tvOS prior to 26.6 and visionOS prior to 26.6
Discovery Timeline
- 2026-07-27 - CVE-2026-64774 published to NVD
- 2026-07-28 - Last updated in NVD database
Technical Details for CVE-2026-64774
Vulnerability Analysis
The vulnerability is an integer overflow [CWE-190] in an Apple operating system component that processes untrusted input from the network. When an attacker supplies crafted values, arithmetic operations on size or length fields wrap around beyond the maximum representable integer. The wrapped value is then used to allocate or index into a heap buffer. Subsequent writes exceed the allocated region, corrupting adjacent heap metadata and object contents.
Heap corruption of this class typically enables control over allocator structures or function pointers. Attackers can chain the primitive with information disclosure or type confusion to achieve remote code execution. Apple's advisories describe the outcome as unexpected application termination or heap corruption, which is consistent with a memory safety flaw reachable from a network-facing attack surface.
Root Cause
The root cause is missing bounds validation on integer values derived from attacker-controlled input. Apple's fix introduces improved input validation to reject or clamp values that would overflow during size calculations. This prevents downstream allocations and copies from operating on truncated or wrapped lengths.
Attack Vector
The attack vector is network-based and requires no privileges or user interaction. A remote attacker sends a crafted payload to a vulnerable service or client component on the target device. Processing the malformed input triggers the arithmetic overflow, producing heap corruption within the affected process.
No public proof-of-concept exploit is available at this time. Apple has not disclosed detailed vulnerable component internals. Consult the Apple Security Support Document #128066 and related advisories for the specific affected component and version details.
Detection Methods for CVE-2026-64774
Indicators of Compromise
- Unexpected crashes or termination of Apple system services or applications, particularly repeated crashes in the same process, recorded in device crash logs.
- Crash reports referencing heap corruption, malloc errors, or libmalloc guard violations on Apple endpoints.
- Anomalous inbound network traffic to Apple devices from untrusted sources immediately preceding process crashes.
Detection Strategies
- Collect and centrally analyze macOS unified logs and crash reports (~/Library/Logs/DiagnosticReports/) for repeated process failures indicative of memory corruption attempts.
- Inventory Apple endpoints and correlate installed OS build numbers against the fixed versions listed in Apple's advisories to identify exposed devices.
- Monitor for unusual network flows to iOS, iPadOS, and macOS devices from external sources, especially traffic patterns preceding application crashes.
Monitoring Recommendations
- Ingest macOS endpoint telemetry, including process crash events and network connection logs, into a centralized analytics platform for correlation.
- Alert on clusters of process terminations across multiple Apple endpoints, which may indicate opportunistic exploitation attempts.
- Track patch compliance across the Apple device fleet and generate alerts when devices remain on vulnerable OS versions beyond a defined SLA.
How to Mitigate CVE-2026-64774
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, or visionOS 26.6 without delay.
- Prioritize internet-exposed and mobile devices used outside the corporate network, as these face the highest exposure to remote attackers.
- Verify patch deployment through mobile device management (MDM) reporting and enforce compliance policies for out-of-date endpoints.
Patch Information
Apple has released patches for all affected platforms. Reference the vendor advisories for platform-specific build numbers and installation instructions: Apple Security Support Document #128066, #128067, #128069, #128070, #128071, and #128072.
Workarounds
- No vendor-supplied workaround is documented. Apply the official OS updates as the primary remediation.
- Restrict network exposure of affected devices where feasible by placing them behind firewalls and disabling unnecessary listening services until patched.
- Enforce MDM policies that require minimum OS versions for access to corporate resources, blocking unpatched devices from sensitive network segments.
# Verify installed macOS version against fixed builds
sw_vers -productVersion
# On iOS/iPadOS devices, confirm version via Settings > General > About
# Ensure version is 26.6 or later (or 15.7.8 / 14.8.8 for supported macOS branches)
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
