CVE-2026-64782: Apple Safari Use-After-Free Vulnerability

CVE-2026-64782 Overview

CVE-2026-64782 is a memory corruption vulnerability affecting Apple Safari and multiple Apple operating systems. The flaw stems from a race condition [CWE-362] in web content processing that Apple resolved through improved locking. Processing maliciously crafted web content can trigger an unexpected Safari crash on affected devices.

Apple addressed the issue in Safari 26.6.1, iOS 18.7.10, iPadOS 18.7.10, iOS 26.6.1, iPadOS 26.6.1, and macOS Tahoe 26.6.2. The vulnerability requires user interaction, such as visiting a crafted web page, and has high attack complexity.

Critical Impact
Successful exploitation leads to an unexpected Safari crash, resulting in denial of service on the browser process.

Affected Products

Apple Safari (versions prior to 26.6.1)
Apple iOS and iPadOS (prior to 18.7.10 and 26.6.1)
Apple macOS Tahoe (prior to 26.6.2)

Discovery Timeline

2026-08-17 - CVE-2026-64782 published to NVD
2026-08-18 - Last updated in NVD database

Technical Details for CVE-2026-64782

Vulnerability Analysis

The vulnerability is a race condition [CWE-362] within the web content processing path used by Safari and Apple's WebKit-based components. Concurrent access to shared state without adequate synchronization allows memory corruption when specific timing conditions are met. Apple's advisory notes the fix was implemented through improved locking, indicating a synchronization defect between threads handling web content.

The observable impact is limited to an unexpected Safari crash. There is no reported disclosure of confidential data or integrity compromise. Exploitation requires user interaction, meaning a target must load attacker-controlled web content in an affected browser or WebView.

The high attack complexity reflects the timing precision needed to trigger the race. Attackers must reliably win the race window against normal thread scheduling on the target device.

Root Cause

The root cause is insufficient locking around shared web content state during concurrent processing. Multiple execution contexts within Safari's rendering pipeline can access the same memory region without serialization. When the race is triggered, memory corruption occurs and the process terminates.

Attack Vector

The attack vector is network-based. An attacker hosts crafted web content on a malicious page or delivers it through a compromised site, advertising network, or embedded WebView. When the victim navigates to the content, Safari attempts to process it and encounters the race condition, causing a crash. No authentication is required, but the victim must actively interact with the content.

No verified public exploit code is available for this issue. See the Apple security advisories referenced below for vendor-supplied technical context.

Detection Methods for CVE-2026-64782

Indicators of Compromise

Repeated or unexpected Safari process crashes correlated with visits to specific URLs or ad-serving domains.
Crash reports referencing WebKit or WebContent processes on iOS, iPadOS, or macOS endpoints.
Anomalous web traffic to newly registered or low-reputation domains preceding browser instability.

Detection Strategies

Collect and analyze macOS and iOS crash logs (ips files, ReportCrash output) for WebKit-related terminations.
Correlate browser crash telemetry with DNS and proxy logs to identify potentially malicious referrers.
Monitor endpoint versions to identify devices running Safari, iOS, iPadOS, or macOS builds below the patched releases.

Monitoring Recommendations

Track Safari and WebKit crash frequency per user and per domain to surface targeted delivery attempts.
Alert on repeated WebContent process exits within short time windows on managed macOS fleets.
Enforce web filtering that blocks known-bad domains and inspects redirect chains from user-clicked links.

How to Mitigate CVE-2026-64782

Immediate Actions Required

Update Safari to 26.6.1 on all managed macOS systems that have not moved to macOS Tahoe 26.6.2.
Update iPhone devices to iOS 18.7.10 or 26.6.1, and iPad devices to iPadOS 18.7.10 or 26.6.1.
Update macOS Tahoe endpoints to 26.6.2.
Inventory devices running vulnerable versions and prioritize patch deployment through mobile device management.

Patch Information

Apple published fixes in Safari 26.6.1, iOS 18.7.10 and iPadOS 18.7.10, iOS 26.6.1 and iPadOS 26.6.1, and macOS Tahoe 26.6.2. Refer to Apple Support Article #148281, Apple Support Article #148282, Apple Support Article #148286, and Apple Support Article #148287 for release specifics.

Workarounds

Restrict browsing on unpatched devices to trusted sites via web filtering or MDM content restrictions.
Disable JavaScript for high-risk users on unpatched Safari installations through Safari advanced settings.
Where feasible, route corporate traffic through a filtering proxy that blocks known malicious payload delivery infrastructure.

bash

# Verify installed Safari version on macOS
mdls -name kMDItemVersion /Applications/Safari.app

# Trigger software update check
sudo softwareupdate --list
sudo softwareupdate --install --all --restart