CVE-2021-1748
📋 TL;DR
This vulnerability allows arbitrary JavaScript code execution when processing malicious URLs due to improper input validation. It affects Apple iOS, iPadOS, tvOS, and watchOS devices. Attackers can exploit this to execute arbitrary code in the context of the affected application.
💻 Affected Systems
- iOS
- iPadOS
- tvOS
- watchOS
📦 What is this software?
Ipados by Apple
Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing data theft, credential harvesting, and installation of persistent malware.
Likely Case
Session hijacking, credential theft, and unauthorized access to device data through malicious web content.
If Mitigated
Limited impact with proper network segmentation and application sandboxing, though code execution still possible.
🎯 Exploit Status
Exploitation requires user interaction (clicking malicious URL) but no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iOS 14.4, iPadOS 14.4, tvOS 14.4, watchOS 7.3
Vendor Advisory: https://support.apple.com/en-us/HT212146
Restart Required: Yes
Instructions:
1. Go to Settings > General > Software Update. 2. Download and install the available update. 3. Restart device when prompted.
🔧 Temporary Workarounds
Disable automatic URL processing
allConfigure devices to not automatically process URLs or use web content filters.
Network filtering
allBlock known malicious URLs at network perimeter using web filters or DNS security.
🧯 If You Can't Patch
- Implement strict web content filtering to block malicious URLs
- Educate users about phishing risks and safe browsing practices
🔍 How to Verify
Check if Vulnerable:
Check device version in Settings > General > About > Version. If version is below iOS 14.4, iPadOS 14.4, tvOS 14.4, or watchOS 7.3, device is vulnerable.Check Version:
Not applicable - check via device settings interfaceVerify Fix Applied:
Verify device version is iOS 14.4+, iPadOS 14.4+, tvOS 14.4+, or watchOS 7.3+ in Settings > General > About > Version.📡 Detection & Monitoring
Log Indicators:
- Unusual URL processing patterns
- JavaScript execution errors in web logs
Network Indicators:
- Requests to known malicious domains delivering exploit payloads
SIEM Query:
Not specifically applicable - monitor for anomalous web traffic patterns