CVE-2021-1864
📋 TL;DR
This is a use-after-free vulnerability in Apple's iOS, iPadOS, watchOS, and tvOS that allows an attacker with JavaScript execution capability to potentially execute arbitrary code. It affects users of Apple devices who visit malicious websites or use compromised web content. The vulnerability could lead to full device compromise.
💻 Affected Systems
- iPhone
- iPad
- Apple Watch
- Apple TV
📦 What is this software?
Ipados by Apple
Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover with arbitrary code execution, potentially leading to data theft, surveillance, or ransomware deployment.
Likely Case
Malicious website could exploit this to install malware, steal credentials, or access sensitive device data.
If Mitigated
With proper patching, the vulnerability is eliminated; with web content filtering, risk is significantly reduced.
🎯 Exploit Status
Requires JavaScript execution, typically via malicious website. No public exploit code known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iOS 14.5, iPadOS 14.5, watchOS 7.4, tvOS 14.5
Vendor Advisory: https://support.apple.com/en-us/HT212317
Restart Required: Yes
Instructions:
1. Go to Settings > General > Software Update. 2. Download and install iOS 14.5/iPadOS 14.5/watchOS 7.4/tvOS 14.5 or later. 3. Restart device after installation.
🔧 Temporary Workarounds
Disable JavaScript
allPrevents JavaScript execution in Safari to block exploitation vector.
Settings > Safari > Advanced > JavaScript > Toggle Off
Use Content Filtering
allBlock access to malicious websites using content filtering solutions.
🧯 If You Can't Patch
- Restrict web browsing to trusted sites only using device management policies.
- Implement network-level web filtering to block malicious content.
🔍 How to Verify
Check if Vulnerable:
Check device version in Settings > General > About > Software Version.Check Version:
Settings > General > About > Software VersionVerify Fix Applied:
Verify version is iOS 14.5+, iPadOS 14.5+, watchOS 7.4+, or tvOS 14.5+.📡 Detection & Monitoring
Log Indicators:
- Unusual Safari/WebKit crashes
- Suspicious JavaScript execution patterns
Network Indicators:
- Connections to known malicious domains serving JavaScript
SIEM Query:
source="apple_device_logs" AND (event="web_crash" OR event="javascript_error")