CVE-2020-9947
📋 TL;DR
CVE-2020-9947 is a use-after-free vulnerability in Apple's WebKit browser engine that allows arbitrary code execution when processing malicious web content. Attackers can exploit this by tricking users into visiting specially crafted websites, potentially taking full control of affected devices. This affects multiple Apple products including iPhones, iPads, Apple Watches, Apple TVs, and Safari/iTunes/iCloud on Windows.
💻 Affected Systems
- iOS
- iPadOS
- watchOS
- tvOS
- Safari
- iTunes for Windows
- iCloud for Windows
📦 What is this software?
Icloud by Apple
Ipados by Apple
Itunes by Apple
Safari by Apple
Tvos by Apple
Watchos by Apple
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the device, allowing data theft, surveillance, ransomware deployment, or persistence establishment.
Likely Case
Drive-by browser exploitation leading to malware installation, credential theft, or unauthorized access to device resources and data.
If Mitigated
Limited impact with proper patch management and security controls; exploitation attempts would be blocked by updated software.
🎯 Exploit Status
Exploitation requires user interaction (visiting malicious website) but no authentication. The CVSS score of 8.8 indicates high exploitability with significant impact.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iOS 14.0+, iPadOS 14.0+, watchOS 7.0+, tvOS 14.0+, Safari 14.0+, iTunes 12.10.9+, iCloud 11.5+
Vendor Advisory: https://support.apple.com/en-us/HT211843
Restart Required: Yes
Instructions:
1. Update iOS/iPadOS to 14.0 or later via Settings > General > Software Update. 2. Update watchOS to 7.0 or later via Watch app on iPhone. 3. Update tvOS to 14.0 or later via Settings > System > Software Updates. 4. Update Safari via macOS Software Update. 5. Update iTunes/iCloud for Windows via Apple Software Update or Microsoft Store.
🔧 Temporary Workarounds
Disable JavaScript
allTemporarily disable JavaScript in Safari to prevent exploitation through web content
Safari > Preferences > Security > uncheck 'Enable JavaScript'
Use Alternative Browser
allUse non-WebKit based browsers (Chrome, Firefox) until patches are applied
🧯 If You Can't Patch
- Restrict web browsing to trusted sites only using content filtering or web proxies
- Implement network segmentation to isolate vulnerable devices from critical systems
🔍 How to Verify
Check if Vulnerable:
Check current version against affected versions: iOS <14.0, iPadOS <14.0, watchOS <7.0, tvOS <14.0, Safari <14.0, iTunes <12.10.9, iCloud <11.5Check Version:
iOS/iPadOS: Settings > General > About > Version; macOS: Safari > About Safari; Windows: iTunes/iCloud > Help > AboutVerify Fix Applied:
Confirm version numbers match or exceed patched versions listed in fix_official section📡 Detection & Monitoring
Log Indicators:
- Safari/WebKit crash logs with memory access violations
- Unexpected process creation from browser processes
- Web content loading from suspicious domains
Network Indicators:
- HTTP requests to known exploit domains
- Unusual outbound connections from browser processes
- Traffic patterns matching drive-by download campaigns
SIEM Query:
source="*safari*" OR source="*webkit*" AND (event_type="crash" OR event_type="process_creation") AND severity>=high🔗 References
- http://www.openwall.com/lists/oss-security/2021/03/22/1
- https://security.gentoo.org/glsa/202104-03
- https://support.apple.com/en-us/HT211843
- https://support.apple.com/en-us/HT211844
- https://support.apple.com/en-us/HT211845
- https://support.apple.com/en-us/HT211850
- https://support.apple.com/en-us/HT211935
- https://support.apple.com/en-us/HT211952
- http://www.openwall.com/lists/oss-security/2021/03/22/1
- https://security.gentoo.org/glsa/202104-03
- https://support.apple.com/en-us/HT211843
- https://support.apple.com/en-us/HT211844
- https://support.apple.com/en-us/HT211845
- https://support.apple.com/en-us/HT211850
- https://support.apple.com/en-us/HT211935
- https://support.apple.com/en-us/HT211952
