CVE-2021-42533
📋 TL;DR
Adobe Bridge versions 11.1.1 and earlier contain a double free vulnerability when processing malicious DCM files. This could allow attackers to execute arbitrary code with the current user's privileges. Exploitation requires user interaction, such as opening a crafted file.
💻 Affected Systems
- Adobe Bridge
📦 What is this software?
Bridge by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through arbitrary code execution with current user privileges, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Local privilege escalation or malware installation if a user opens a malicious DCM file, potentially compromising the workstation.
If Mitigated
Limited impact with proper application sandboxing, least privilege principles, and user awareness training about opening untrusted files.
🎯 Exploit Status
Exploitation requires user interaction to open a malicious DCM file. Double free vulnerabilities can be challenging to exploit reliably.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 11.1.2 or later
Vendor Advisory: https://helpx.adobe.com/security/products/bridge/apsb21-94.html
Restart Required: Yes
Instructions:
1. Open Adobe Creative Cloud application. 2. Navigate to 'Apps' tab. 3. Find Adobe Bridge and click 'Update'. 4. Alternatively, download the update directly from Adobe's website. 5. Restart the application after installation.
🔧 Temporary Workarounds
Disable DCM file association
allRemove Adobe Bridge as the default handler for DCM files to prevent automatic opening.
Windows: Control Panel > Default Programs > Associate a file type or protocol with a program > Change .dcm association
macOS: Right-click DCM file > Get Info > Open with > Change to different application
🧯 If You Can't Patch
- Implement application whitelisting to block execution of Adobe Bridge
- Use endpoint protection with memory corruption exploit prevention capabilities
🔍 How to Verify
Check if Vulnerable:
Check Adobe Bridge version in Help > About Adobe Bridge. If version is 11.1.1 or earlier, the system is vulnerable.Check Version:
Windows: "C:\Program Files\Adobe\Adobe Bridge\Bridge.exe" --version (if available) or check in application. macOS: /Applications/Adobe Bridge/Bridge.app/Contents/Info.plist or check in application.Verify Fix Applied:
Verify Adobe Bridge version is 11.1.2 or later in Help > About Adobe Bridge.📡 Detection & Monitoring
Log Indicators:
- Application crashes of Adobe Bridge
- Process creation from Adobe Bridge with unusual command lines
- File access to DCM files followed by process termination
Network Indicators:
- Outbound connections from Adobe Bridge process to suspicious IPs post-crash
SIEM Query:
Process:Name="Bridge.exe" AND (EventID=1000 OR EventID=1001) OR FileAccess:Extension="dcm" AND Process:Name="Bridge.exe"