CVE-2026-64757 Overview
CVE-2026-64757 is a memory corruption vulnerability affecting Apple's WebKit-based Safari browser and multiple Apple operating systems. Processing maliciously crafted web content triggers memory corruption that can lead to an unexpected Safari crash. Apple resolved the issue through improved state management in Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, visionOS 26.6, and watchOS 26.6.
The flaw is classified under [CWE-119] (Improper Restriction of Operations within the Bounds of a Memory Buffer). The attack vector is network-based and requires user interaction, such as visiting an attacker-controlled webpage.
Critical Impact
Remote attackers can trigger memory corruption in Safari by luring users to malicious web content, potentially leading to crashes and possible code execution scenarios.
Affected Products
- Apple Safari (prior to 26.6)
- Apple iOS and iPadOS (prior to 26.6)
- Apple macOS Tahoe (prior to 26.6)
- Apple visionOS and watchOS (prior to 26.6)
Discovery Timeline
- 2026-07-27 - CVE-2026-64757 published to NVD
- 2026-07-28 - Last updated in NVD database
Technical Details for CVE-2026-64757
Vulnerability Analysis
CVE-2026-64757 stems from improper state management in Safari's web content processing pipeline. When Safari parses maliciously crafted web content, internal state transitions occur in an unexpected order, leading to memory corruption. Apple addressed the root defect by tightening state management logic in the affected component.
The issue falls under the [CWE-119] category, meaning that operations on memory buffers can exceed intended boundaries. Attackers exploiting this class of flaw in a browser engine can trigger crashes and, in some cases, escalate to arbitrary code execution within the renderer sandbox.
The vulnerability affects Apple's shared web rendering stack, which explains the wide range of affected platforms including desktop, mobile, tablet, wearable, and mixed-reality operating systems.
Root Cause
The root cause is a state management defect in the Safari/WebKit engine. Specific object states were not correctly validated across transitions, allowing corrupted memory conditions to occur when specific sequences of web content operations were processed. Apple's advisories describe the remediation as "improved state management," indicating the fix synchronizes and validates state before memory operations proceed.
Attack Vector
Exploitation requires a victim to visit or interact with attacker-controlled web content. An attacker hosts a malicious page containing crafted HTML, JavaScript, or media that triggers the vulnerable code path in Safari or WebKit. No privileges are required on the target system, but user interaction (loading the page) is mandatory. Successful exploitation causes Safari to crash and may enable further memory corruption abuse.
No public proof-of-concept or exploit is currently available, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Detection Methods for CVE-2026-64757
Indicators of Compromise
- Repeated or unexpected Safari crashes on macOS, iOS, iPadOS, visionOS, or watchOS devices following web browsing sessions.
- Crash reports referencing WebKit or Safari renderer processes with memory corruption signatures.
- Connections from managed devices to newly registered or low-reputation domains hosting active web content.
Detection Strategies
- Monitor endpoint crash telemetry for com.apple.WebKit and Safari process terminations correlated with web browsing activity.
- Ingest macOS unified logs and iOS device management crash data into a SIEM to identify clustered crash events across users.
- Correlate web proxy logs with device crash timestamps to identify potential attacker infrastructure delivering malicious content.
Monitoring Recommendations
- Track Safari and WebKit version compliance across the fleet via MDM to identify devices below version 26.6.
- Alert on outbound traffic to domains flagged by threat intelligence feeds for browser exploit hosting.
- Review browser telemetry for anomalous JavaScript execution patterns or repeated renderer restarts.
How to Mitigate CVE-2026-64757
Immediate Actions Required
- Update all Apple devices to Safari 26.6, iOS 26.6, iPadOS 26.6, macOS Tahoe 26.6, visionOS 26.6, and watchOS 26.6.
- Enforce update compliance through Mobile Device Management (MDM) policies for enrolled devices.
- Educate users about avoiding untrusted links and web content until patches are applied.
Patch Information
Apple released fixes across its product line. Consult the vendor advisories for platform-specific update instructions: Apple Security Advisory #128066, Apple Security Advisory #128067, Apple Security Advisory #128068, Apple Security Advisory #128070, and Apple Security Advisory #128073. Verify installed versions on each device before considering remediation complete.
Workarounds
- Restrict Safari usage on unpatched devices and route web traffic through a filtered browser or secure web gateway.
- Apply web content filtering to block access to unknown or high-risk domains until updates are applied.
- Consider temporarily using an alternate browser on macOS for high-risk users until patching is confirmed.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
