CVE-2021-40720
📋 TL;DR
CVE-2021-40720 is a critical deserialization vulnerability in Adobe Ops CLI that allows arbitrary code execution when processing malicious files. Attackers can exploit this to run commands on affected systems. Users of Adobe Ops CLI versions 2.0.4 and earlier are vulnerable.
💻 Affected Systems
- Adobe Ops CLI
📦 What is this software?
Ops Cli by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise with attacker gaining complete control over the victim machine, enabling data theft, lateral movement, and persistent access.
Likely Case
Execution of arbitrary commands with the privileges of the Ops CLI user, potentially leading to data exfiltration, credential harvesting, or deployment of malware.
If Mitigated
Limited impact if proper network segmentation and least privilege principles are applied, though local exploitation risk remains.
🎯 Exploit Status
Exploitation requires user interaction to process malicious files, but the technical complexity is low once malicious input is provided.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.0.5
Vendor Advisory: https://helpx.adobe.com/security/products/ops_cli/apsb21-88.html
Restart Required: No
Instructions:
1. Download Ops CLI version 2.0.5 or later from Adobe's official distribution channels. 2. Uninstall the vulnerable version. 3. Install the patched version following Adobe's installation guide.
🔧 Temporary Workarounds
Avoid Untrusted File Processing
allDo not use checkout_repo function with files from untrusted sources
Restrict Ops CLI Usage
allLimit Ops CLI usage to trusted environments and users
🧯 If You Can't Patch
- Implement strict file validation and only process files from trusted sources
- Run Ops CLI with minimal user privileges and in isolated environments
🔍 How to Verify
Check if Vulnerable:
Check Ops CLI version using 'ops --version' command. If version is 2.0.4 or earlier, system is vulnerable.Check Version:
ops --versionVerify Fix Applied:
After updating, run 'ops --version' to confirm version is 2.0.5 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual process execution from Ops CLI
- File processing errors in Ops CLI logs
- Suspicious network connections initiated by Ops CLI
Network Indicators:
- Outbound connections to unexpected destinations from systems running Ops CLI
SIEM Query:
Process execution where parent_process contains 'ops' AND command_line contains suspicious patterns