CVE-2026-64718: Apple Safari Use-After-Free Vulnerability

CVE-2026-64718 Overview

CVE-2026-64718 is a use-after-free vulnerability [CWE-416] in Apple's web content processing components. Processing maliciously crafted web content may trigger an unexpected Safari crash, resulting in denial of service on the affected device. Apple addressed the flaw through improved memory management across its product family. The issue impacts Safari and all major Apple operating systems, including iOS, iPadOS, macOS, tvOS, visionOS, and watchOS. Exploitation requires user interaction, typically visiting a crafted web page.

Critical Impact
Successful exploitation causes an unexpected Safari crash when processing maliciously crafted web content, disrupting browser availability on affected Apple devices.

Affected Products

Apple Safari (versions prior to 26.6)
Apple iOS and iPadOS (versions prior to 26.6)
Apple macOS Tahoe (versions prior to 26.6), tvOS, visionOS, and watchOS (versions prior to 26.6)

Discovery Timeline

2026-07-27 - CVE-2026-64718 published to NVD
2026-07-29 - Last updated in NVD database

Technical Details for CVE-2026-64718

Vulnerability Analysis

The vulnerability is a use-after-free condition in Apple's web content processing stack, reachable when Safari or WebKit-based components parse crafted web content. A use-after-free defect occurs when code continues to reference memory after it has been freed, allowing the freed allocation to be reused for unrelated data. When the dangling pointer is dereferenced, the process reads or writes an object it does not own, producing memory corruption. In this case, the observable outcome is an unexpected Safari crash, consistent with a high-availability impact and no confidentiality or integrity loss.

Root Cause

The root cause is improper lifetime management of an object within Safari's web content processing routines. Apple's advisory notes the fix was implemented through improved memory management, indicating the code path failed to invalidate or reference-count an object correctly before subsequent access. The defect is tracked under CWE-416: Use After Free.

Attack Vector

Exploitation requires user interaction. A victim must load attacker-controlled web content in Safari or a component that renders HTML using the affected WebKit-based engine. Attack complexity is low and no privileges are required, but the vector is scored as local because the malicious content is processed by the local rendering process. Based on the current CVSS assessment, the demonstrated impact is limited to a crash rather than arbitrary code execution.

No public proof-of-concept or exploit code is available for CVE-2026-64718 at the time of publication, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog. See the Apple security advisories for vendor-provided technical context.

Detection Methods for CVE-2026-64718

Indicators of Compromise

Repeated or unexpected Safari or WebKit process crashes on macOS, iOS, or iPadOS endpoints, particularly following navigation to untrusted URLs.
Crash reports referencing WebKit content process termination with memory access violations in com.apple.WebKit.WebContent or related frameworks.
Endpoints running Safari, iOS, iPadOS, macOS, tvOS, visionOS, or watchOS versions earlier than 26.6.

Detection Strategies

Inventory Apple endpoints and flag any device running an OS or Safari build below 26.6 as vulnerable.
Correlate browser crash telemetry with recent web navigation events to identify potential exploitation attempts.
Monitor DNS and proxy logs for connections to newly registered or low-reputation domains preceding WebKit crash events.

Monitoring Recommendations

Ingest macOS and iOS unified logs and crash reports into a central analytics platform to detect abnormal Safari termination patterns.
Alert on clusters of WebKit content process crashes across multiple users pointing to a common URL or domain.
Track patch compliance for Apple software updates and generate weekly reports on outstanding devices.

How to Mitigate CVE-2026-64718

Immediate Actions Required

Update to Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6 on all affected devices.
Prioritize patching for users who routinely browse untrusted content or handle sensitive data on Apple endpoints.
Validate deployment by confirming Safari and OS versions after update through mobile device management (MDM) reporting.

Patch Information

Apple resolved CVE-2026-64718 with improved memory management in Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6. Refer to the vendor advisories for platform-specific details: Apple Support #128066, #128067, #128068, #128069, #128070, and #128073.

Workarounds

Restrict browsing to trusted sites until the update is deployed, since the vulnerability requires processing crafted web content.
Enforce web filtering and DNS-layer controls through your existing security stack to block known malicious domains.
Use MDM policies to require the latest Safari and OS versions before granting access to corporate resources.

bash

# Verify macOS and Safari versions on a managed endpoint
sw_vers -productVersion
defaults read /Applications/Safari.app/Contents/Info.plist CFBundleShortVersionString

# Trigger a software update check via MDM or locally
sudo softwareupdate --list
sudo softwareupdate --install --all --restart