CVE-2021-21092
📋 TL;DR
This vulnerability allows arbitrary code execution via memory corruption when Adobe Bridge parses a malicious file. Attackers can exploit this by tricking users into opening specially crafted files, affecting users of vulnerable Adobe Bridge versions. The vulnerability requires user interaction but executes code with the current user's privileges.
💻 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, leading to data theft, ransomware deployment, or lateral movement within the network.
Likely Case
Local privilege escalation leading to data exfiltration, malware installation, or persistence mechanisms being established on the compromised system.
If Mitigated
Limited impact with proper application whitelisting and user training preventing malicious file execution, though system remains vulnerable to targeted attacks.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) but no authentication. Memory corruption vulnerabilities typically require some exploit development skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Bridge 10.1.2, Bridge 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. Install available updates. 4. Restart Adobe Bridge. Alternatively, download and install the latest version from Adobe's website.
🔧 Temporary Workarounds
Disable Bridge file associations
allPrevent Bridge from automatically opening potentially malicious file types
Windows: Control Panel > Default Programs > Associate a file type or protocol with a program
macOS: Finder > Get Info > Open With > Change All
Application control policies
allRestrict Bridge from executing untrusted files via group policy or endpoint protection
Windows: gpedit.msc > Computer Configuration > Windows Settings > Security Settings > Application Control Policies
macOS: System Preferences > Security & Privacy > Privacy > Full Disk Access
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of unauthorized files
- Deploy email/web filtering to block malicious file attachments and downloads
🔍 How to Verify
Check if Vulnerable:
Check Adobe Bridge version in Help > About Adobe Bridge. If version is 10.1.1 or earlier, or 11.0.1 or earlier, the system is vulnerable.Check Version:
Windows: "C:\Program Files\Adobe\Adobe Bridge\Bridge.exe" --version (if installed in default location) | macOS: /Applications/Adobe Bridge/Bridge.app/Contents/MacOS/Bridge --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 process crashes
- Suspicious file opens in Bridge logs
- Unusual child processes spawned from Bridge
Network Indicators:
- Outbound connections from Bridge to unknown IPs
- DNS requests for suspicious domains from Bridge process
SIEM Query:
process_name:"Bridge.exe" AND (event_type:process_crash OR parent_process:"Bridge.exe")