CVE-2021-21094
📋 TL;DR
CVE-2021-21094 is an out-of-bounds write vulnerability in Adobe Bridge that allows arbitrary code execution when parsing malicious files. Attackers can exploit this by tricking users into opening specially crafted files, potentially taking full control of the affected system. Users of Adobe Bridge versions 10.1.1 and earlier or 11.0.1 and earlier are affected.
💻 Affected Systems
- Adobe Bridge
📦 What is this software?
Bridge by Adobe
Bridge by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control of the victim's computer, enabling data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Malware installation leading to data exfiltration, credential theft, or system disruption through user interaction with malicious files.
If Mitigated
Limited impact with proper patching and user awareness training preventing successful exploitation.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but is otherwise straightforward once the file format is understood.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Bridge 10.1.2 or 11.0.2
Vendor Advisory: https://helpx.adobe.com/security/products/bridge/apsb21-23.html
Restart Required: Yes
Instructions:
1. Open Adobe Bridge. 2. Go to Help > Updates. 3. Follow prompts to install Bridge 10.1.2 or 11.0.2. 4. Restart the application.
🔧 Temporary Workarounds
Disable Bridge file parsing
allPrevent Bridge from automatically opening or parsing unknown file types
User awareness training
allTrain users not to open files from untrusted sources
🧯 If You Can't Patch
- Restrict user permissions to limit impact of code execution
- Implement application whitelisting to prevent unauthorized executables
🔍 How to Verify
Check if Vulnerable:
Check Adobe Bridge version in Help > About Adobe BridgeCheck Version:
On Windows: wmic product where name="Adobe Bridge" get versionVerify Fix Applied:
Verify version is 10.1.2 or higher for Bridge 10.x, or 11.0.2 or higher for Bridge 11.x📡 Detection & Monitoring
Log Indicators:
- Unexpected Bridge crashes
- Suspicious file access patterns
- Unusual process creation from Bridge
Network Indicators:
- Outbound connections from Bridge to unknown IPs
- DNS requests to suspicious domains
SIEM Query:
process_name:"bridge.exe" AND (event_type:crash OR parent_process:unusual)