CVE-2024-54534: Apple Safari Use-After-Free Vulnerability

CVE-2024-54534 Overview

CVE-2024-54534 is a memory corruption vulnerability affecting Apple's WebKit browser engine across multiple Apple platforms. The vulnerability stems from improper memory handling when processing maliciously crafted web content. An attacker could exploit this flaw by enticing a victim to visit a specially crafted website, potentially leading to arbitrary code execution or system compromise.

This Out-of-Bounds Write (CWE-787) vulnerability affects the core browser rendering engine used across Apple's ecosystem, making it particularly impactful given the widespread deployment of Safari and WebKit-based browsers on Apple devices.

Critical Impact

Processing maliciously crafted web content may lead to memory corruption, potentially enabling remote code execution across all affected Apple platforms including iOS, macOS, watchOS, tvOS, and visionOS.

Affected Products

• Apple Safari (versions prior to 18.2)
• Apple iOS and iPadOS (versions prior to 18.2)
• Apple macOS Sequoia (versions prior to 15.2)
• Apple watchOS (versions prior to 11.2)
• Apple tvOS (versions prior to 18.2)
• Apple visionOS (versions prior to 2.2)

Discovery Timeline

• December 12, 2024 - CVE-2024-54534 published to NVD
• November 3, 2025 - Last updated in NVD database

Technical Details for CVE-2024-54534

Vulnerability Analysis

This vulnerability is classified as an Out-of-Bounds Write (CWE-787), which occurs when WebKit's memory handling routines fail to properly validate boundaries during web content processing. When a user visits a malicious webpage, the browser engine may write data beyond the allocated memory buffer, corrupting adjacent memory regions.

The vulnerability resides in the WebKit rendering engine, which is the foundation for Safari and is embedded in all Apple operating systems for web content rendering. This architectural decision means that the vulnerability extends beyond just the Safari browser to affect any application that uses WebKit for content display.

The attack can be executed remotely over the network without requiring any privileges or user authentication. An attacker simply needs to host malicious web content and convince a victim to navigate to the malicious URL. No user interaction beyond visiting the page is required for exploitation.

Root Cause

The root cause of CVE-2024-54534 lies in insufficient bounds checking within WebKit's memory allocation and management routines. When processing certain types of web content, the engine fails to properly validate the size of data being written against the allocated buffer size. This allows an attacker to craft content that triggers writes beyond the intended memory boundaries, leading to memory corruption.

Apple addressed this issue with improved memory handling, implementing stricter boundary validation and safer memory management practices within the affected code paths.

Attack Vector

The attack vector for this vulnerability is network-based, requiring no authentication or special privileges. An attacker can exploit this vulnerability through the following scenario:

1. The attacker creates a malicious website hosting specially crafted web content designed to trigger the memory corruption
2. The victim is enticed to visit the malicious website through phishing, social engineering, or malvertising
3. When the victim's browser (Safari) or any WebKit-based application loads the malicious content, the out-of-bounds write occurs
4. The memory corruption can lead to arbitrary code execution in the context of the browser process

The vulnerability mechanism exploits WebKit's content rendering pipeline. When maliciously crafted web content is processed, improper boundary validation allows memory writes to occur outside allocated buffers. This corruption can be leveraged to overwrite critical memory structures, potentially leading to control flow hijacking and arbitrary code execution. For detailed technical information, refer to the Apple Security Support documentation.

Detection Methods for CVE-2024-54534

Indicators of Compromise

• Unexpected browser crashes or memory access violations when visiting specific websites
• Unusual WebKit process behavior including abnormal memory consumption patterns
• Safari or WebKit-based applications exhibiting instability after visiting unknown URLs
• System logs indicating memory corruption or segmentation faults in WebKit processes

Detection Strategies

• Monitor for Safari and WebKit process crashes with memory-related error codes in system logs
• Deploy network security solutions to analyze and block known malicious web content patterns
• Implement endpoint detection rules to identify WebKit processes with anomalous memory access patterns
• Utilize SentinelOne's behavioral AI to detect exploitation attempts targeting browser vulnerabilities

Monitoring Recommendations

• Enable crash reporting on all Apple devices to capture WebKit-related crash data for analysis
• Deploy web proxy solutions with deep content inspection to identify potential exploitation attempts
• Monitor for unusual outbound network connections following browser crashes
• Review system logs (/var/log/system.log on macOS) for WebKit-related memory errors

How to Mitigate CVE-2024-54534

Immediate Actions Required

• Update all Apple devices to the latest available OS versions immediately
• Ensure Safari is updated to version 18.2 or later on all systems
• Advise users to avoid visiting untrusted websites until patches are applied
• Consider using content filtering to block access to known malicious domains

Patch Information

Apple has released security updates to address this vulnerability across all affected platforms. Organizations should prioritize deployment of these patches:

Additional security information is available in the NetApp Security Advisory NTAP-20250418-0002.

Workarounds

• If immediate patching is not possible, consider using alternative browsers that do not rely on WebKit for critical operations
• Implement strict web content filtering policies to block potentially malicious sites
• Enable heightened security controls such as content blockers and JavaScript restrictions where feasible
• Limit browsing to trusted, known-safe websites until patches can be applied

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

# Verify macOS version
sw_vers -productVersion

# Check for available updates on macOS
softwareupdate --list

# Install all available updates
softwareupdate --install --all