CVE-2026-65337 Overview
CVE-2026-65337 is an improper input validation vulnerability [CWE-20] affecting Apple Safari and multiple Apple operating systems. Processing maliciously crafted web content can trigger an unexpected Safari crash, resulting in a denial-of-service condition. Apple addressed the issue through improved state management in the affected components.
The flaw requires user interaction, such as visiting an attacker-controlled webpage, and does not impact confidentiality or integrity. Apple has released fixes 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.
Critical Impact
Attackers can crash Safari on unpatched Apple devices by luring users to malicious web content, degrading browser availability across iOS, iPadOS, and macOS.
Affected Products
- Apple Safari (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-2026-65337 published to the National Vulnerability Database (NVD)
- 2026-08-18 - Last updated in NVD database
Technical Details for CVE-2026-65337
Vulnerability Analysis
CVE-2026-65337 originates in Safari's handling of specially crafted web content. Apple's advisory attributes the fix to improved state management, indicating that the browser transitioned into an inconsistent internal state when processing certain inputs. That inconsistent state caused an unexpected process termination.
The issue is classified under improper input validation [CWE-20]. The browser accepted or processed content that violated expected constraints, leading the rendering engine to reach an unrecoverable condition. Exploitation yields a crash rather than code execution, which limits impact to availability of the Safari process on the affected device.
Root Cause
The root cause is inadequate state tracking within Safari's web content processing pipeline. When the browser encountered maliciously crafted markup, script, or media content, internal state assumptions were violated. Apple's remediation reinforces state validation to prevent the browser from continuing execution in an invalid state.
Attack Vector
The attack vector is network-based and requires user interaction. An attacker hosts malicious content on a webpage or delivers it through an embedded resource such as an iframe or advertisement. When the victim loads the content in a vulnerable Safari build, the browser tab or process crashes. There is no evidence of exploitation in the wild, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Refer to the Apple Support Document #148281, #148282, #148286, and #148287 for vendor technical details.
Detection Methods for CVE-2026-65337
Indicators of Compromise
- Repeated Safari process termination events (com.apple.Safari or WebContent) on macOS coinciding with visits to untrusted URLs.
- Diagnostic crash reports referencing WebKit rendering components generated shortly after page navigation on iOS or iPadOS.
- Elevated user reports of Safari tab crashes across a fleet after browsing specific external domains.
Detection Strategies
- Correlate endpoint crash telemetry from macOS Unified Log with browser process names to identify abnormal Safari termination rates.
- Inspect web proxy and DNS logs for outbound connections to newly registered or low-reputation domains preceding browser crashes.
- Monitor MDM software inventory to flag devices still running Safari, iOS, iPadOS, or macOS versions prior to the fixed builds.
Monitoring Recommendations
- Ingest macOS ReportCrash and mobile device crash telemetry into a centralized log platform for trend analysis.
- Track user-agent strings from corporate egress traffic to enforce browser version compliance.
- Alert on unpatched device counts and prioritize remediation for high-value user groups such as executives and developers.
How to Mitigate CVE-2026-65337
Immediate Actions Required
- Update Safari to version 26.6.1 on macOS builds where a standalone Safari update is available.
- Upgrade iOS and iPadOS devices to 18.7.10 or 26.6.1, depending on the supported major release.
- Upgrade macOS Tahoe endpoints to 26.6.2 to receive the integrated WebKit fixes.
- Communicate to users the risk of loading untrusted web content on devices pending update.
Patch Information
Apple released patches on the schedule referenced in support documents 148281, 148282, 148286, and 148287. The fixed versions are 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. Deploy updates through Apple Software Update, MDM, or Apple Business Manager to ensure coverage across managed fleets.
Workarounds
- Restrict browsing to trusted domains through enterprise web filtering until updates are deployed.
- Enforce content policies at the network edge to block known malicious domains and low-reputation web categories.
- Encourage users to use alternate browsers on unpatched macOS systems if business workflows permit.
# Verify Safari version on macOS
mdls -name kMDItemVersion /Applications/Safari.app
# Check macOS build
sw_vers
# Trigger managed software updates via MDM command (example)
sudo softwareupdate --install --all --restart
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
