CVE-2020-9633
📋 TL;DR
CVE-2020-9633 is a use-after-free vulnerability in Adobe Flash Player that allows attackers to execute arbitrary code on affected systems. This affects Flash Player Desktop Runtime, Flash Player for Google Chrome, and Flash Player for Microsoft Edge/Internet Explorer. Successful exploitation could lead to complete system compromise.
💻 Affected Systems
- Adobe Flash Player Desktop Runtime
- Adobe Flash Player for Google Chrome
- Adobe Flash Player for Microsoft Edge
- Adobe Flash Player for Internet Explorer
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the victim's machine, enabling data theft, ransomware deployment, or lateral movement within networks.
Likely Case
Remote code execution leading to malware installation, credential theft, or system disruption for targeted attacks.
If Mitigated
Limited impact if Flash Player is disabled or removed, with potential browser sandbox escape but restricted system access.
🎯 Exploit Status
Use-after-free vulnerabilities in Flash Player have historically been exploited in the wild via drive-by downloads and malicious websites.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Flash Player 32.0.0.372 or later
Vendor Advisory: https://helpx.adobe.com/security/products/flash-player/apsb20-30.html
Restart Required: Yes
Instructions:
1. Update Flash Player through Adobe's update mechanism or download from Adobe's website. 2. For browser-embedded versions, update Chrome, Edge, or Internet Explorer to latest versions. 3. Restart browser/system after update.
🔧 Temporary Workarounds
Disable Flash Player in browsers
allPrevent Flash content from executing in web browsers
Chrome: chrome://settings/content/flash → Block
Edge: edge://settings/content/flash → Block
IE: Internet Options → Programs → Manage add-ons → Disable Shockwave Flash Object
Uninstall Flash Player
allRemove Flash Player completely from system
Windows: Control Panel → Programs → Uninstall Adobe Flash Player
macOS: sudo rm -rf /Library/Internet\ Plug-Ins/Flash\ Player.plugin
Linux: sudo apt remove adobe-flashplugin
🧯 If You Can't Patch
- Disable Flash Player in all browsers and applications
- Implement network filtering to block Flash content and restrict internet access for vulnerable systems
🔍 How to Verify
Check if Vulnerable:
Check Flash Player version in browser settings or system control panel. Version 32.0.0.371 or earlier for Desktop/Chrome, or 32.0.0.330 or earlier for Edge/IE indicates vulnerability.Check Version:
Windows: reg query "HKLM\SOFTWARE\Macromedia\FlashPlayer" /v Version; Linux: dpkg -l | grep flash; Browser: Visit about:plugins or chrome://componentsVerify Fix Applied:
Confirm Flash Player version is 32.0.0.372 or later. Test with Flash content to ensure functionality while monitoring for crashes.📡 Detection & Monitoring
Log Indicators:
- Flash Player crash logs
- Browser crash reports with Flash-related modules
- Unexpected process creation from browser processes
Network Indicators:
- Requests to Flash content (.swf files) from untrusted sources
- Unusual outbound connections from browsers
SIEM Query:
process_name:chrome.exe AND parent_process:explorer.exe AND command_line:*flash* OR process_name:flashplayer*