CVE-2024-23213: Apple Safari RCE Vulnerability

CVE-2024-23213 Overview

CVE-2024-23213 is a memory handling vulnerability affecting Apple's WebKit browser engine and multiple Apple operating systems. The flaw exists in how WebKit processes web content, allowing attackers to potentially execute arbitrary code on affected devices. This vulnerability impacts a wide range of Apple products including Safari, iOS, iPadOS, macOS, tvOS, and watchOS, making it a significant security concern for the Apple ecosystem.

Critical Impact

Processing maliciously crafted web content may lead to arbitrary code execution, potentially allowing attackers to take control of affected devices through drive-by browser attacks.

Affected Products

• Apple Safari versions prior to 17.3
• Apple iOS versions prior to 17.3 and iOS 16.7.5
• Apple iPadOS versions prior to 17.3 and iPadOS 16.7.5
• Apple macOS Sonoma versions prior to 14.3
• Apple tvOS versions prior to 17.3
• Apple watchOS versions prior to 10.3

Discovery Timeline

• January 23, 2024 - CVE-2024-23213 published to NVD
• June 20, 2025 - Last updated in NVD database

Technical Details for CVE-2024-23213

Vulnerability Analysis

This vulnerability stems from improper memory handling within WebKit, Apple's open-source web browser engine that powers Safari and serves as the foundation for web content rendering across all Apple platforms. The flaw is classified under CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), indicating that the vulnerability involves memory safety issues where data can be written or read outside intended buffer boundaries.

The attack requires user interaction—specifically, a victim must visit a malicious website or be redirected to attacker-controlled web content. Once triggered, the vulnerability can lead to arbitrary code execution within the context of the browser process. Given WebKit's privileged position in processing all web content on Apple devices, successful exploitation could result in significant system compromise including data theft, installation of malware, or further privilege escalation.

The vulnerability affects both current and legacy iOS branches (iOS 17.x and iOS 16.x), indicating the flaw exists in shared WebKit code that has been present across multiple release cycles.

Root Cause

The root cause of CVE-2024-23213 is improper memory handling within WebKit's web content processing routines. Memory handling vulnerabilities in browser engines typically occur during complex operations such as JavaScript execution, DOM manipulation, or rendering of specific HTML/CSS constructs. When memory is not properly allocated, tracked, or freed during these operations, it can lead to conditions where attackers can manipulate memory state to achieve code execution.

Apple addressed this issue with improved memory handling, suggesting the fix involved adding proper bounds checking, memory allocation validation, or correcting how memory resources are managed during web content processing.

Attack Vector

The attack vector for this vulnerability is network-based, requiring the victim to process malicious web content. Exploitation scenarios include:

1. Drive-by download attacks - Victim visits a compromised or malicious website hosting exploit code
2. Malicious advertisements - Exploit code delivered through advertising networks on legitimate websites
3. Phishing campaigns - Targeted emails containing links to exploit pages
4. Man-in-the-middle attacks - Injecting exploit code into HTTP traffic

The vulnerability requires user interaction (visiting a malicious page) but no authentication or special privileges. Once the malicious content is processed by the vulnerable WebKit engine, arbitrary code execution can occur without additional user consent.

Due to the sensitive nature of this vulnerability and the lack of verified proof-of-concept code in public repositories, specific exploitation techniques are not detailed here. Security teams should refer to Apple's security advisories for technical guidance on the vulnerability mechanics.

Detection Methods for CVE-2024-23213

Indicators of Compromise

• Unexpected Safari or WebKit process crashes followed by suspicious system behavior
• Unusual network connections originating from browser processes to unknown external hosts
• Presence of unexpected processes spawned as children of Safari or WebKit-related services
• Memory corruption artifacts in crash reports referencing WebKit components

Detection Strategies

• Monitor for WebKit crash reports that indicate memory corruption patterns in system logs
• Implement network monitoring for connections to known malicious infrastructure following browser activity
• Deploy endpoint detection rules to identify suspicious child processes spawned by Safari or other WebKit-based applications
• Review system logs for unusual privilege escalation attempts following web browsing sessions

Monitoring Recommendations

• Enable detailed logging on Apple devices using profiles or MDM solutions to capture WebKit-related events
• Configure SIEM rules to correlate browser crashes with subsequent suspicious activity
• Monitor for updates to Apple devices and ensure patch compliance across the fleet
• Subscribe to Apple security bulletins and threat intelligence feeds for emerging exploitation activity

How to Mitigate CVE-2024-23213

Immediate Actions Required

• Update all Apple devices to the patched versions: Safari 17.3, iOS 17.3/16.7.5, iPadOS 17.3/16.7.5, macOS Sonoma 14.3, tvOS 17.3, and watchOS 10.3
• Prioritize patching devices with internet-facing browsers and those used for accessing untrusted content
• Verify update installation through device settings or MDM reporting dashboards
• Educate users about the risks of visiting untrusted websites until patches are applied

Patch Information

Apple has released security updates addressing this vulnerability across all affected platforms. The patches implement improved memory handling to prevent the exploitation of this vulnerability. Detailed information is available in Apple's security advisories:

• Apple Security Update HT214055 - Safari 17.3
• Apple Security Update HT214056 - iOS 17.3 and iPadOS 17.3
• Apple Security Update HT214059 - iOS 16.7.5 and iPadOS 16.7.5
• Apple Security Update HT214060 - macOS Sonoma 14.3
• Apple Security Update HT214061 - watchOS 10.3
• Apple Security Update HT214063 - tvOS 17.3

Additionally, Fedora has released updates for WebKitGTK packages. See the Fedora Package Announcements for Linux-based WebKit updates.

Workarounds

• Restrict access to untrusted websites through web filtering or proxy solutions until patches can be applied
• Consider using alternative browsers on macOS as a temporary measure (though WebKit is still used system-wide for certain functions)
• Implement content security policies on enterprise web properties to reduce exploit delivery surface
• Use network segmentation to limit potential lateral movement if exploitation occurs

# Check Safari version on macOS
/Applications/Safari.app/Contents/MacOS/Safari --version

# Check iOS/iPadOS version via command line (if accessible)
# Settings > General > About > Software Version

# Verify macOS version
sw_vers -productVersion

# Force software update check on macOS
softwareupdate --list