CVE-2021-32849
📋 TL;DR
CVE-2021-32849 is an authenticated remote code execution vulnerability in Gerapy, a distributed crawler management framework. Authenticated users can execute arbitrary commands on the server due to improper input validation. This affects all Gerapy deployments prior to version 0.9.9.
💻 Affected Systems
- Gerapy
📦 What is this software?
Gerapy by Gerapy
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise allowing attackers to execute arbitrary commands with the privileges of the Gerapy process, potentially leading to data theft, lateral movement, or complete system takeover.
Likely Case
Attackers with valid credentials can execute commands to exfiltrate sensitive data, deploy malware, or pivot to other systems in the network.
If Mitigated
With proper network segmentation and least privilege access, impact is limited to the Gerapy application and its data.
🎯 Exploit Status
Exploitation requires valid credentials. Public proof-of-concept code exists in GitHub advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.9.9
Vendor Advisory: https://github.com/Gerapy/Gerapy/security/advisories/GHSA-756h-r2c9-qp5j
Restart Required: Yes
Instructions:
1. Backup your Gerapy configuration and data. 2. Stop the Gerapy service. 3. Upgrade to version 0.9.9 using pip: 'pip install gerapy==0.9.9'. 4. Restart the Gerapy service.
🔧 Temporary Workarounds
No known workarounds
allThe vendor advisory states there are no known workarounds. Upgrading is the only solution.
🧯 If You Can't Patch
- Isolate Gerapy instances from critical systems using network segmentation
- Implement strict access controls and monitor for unusual authentication attempts
🔍 How to Verify
Check if Vulnerable:
Check Gerapy version: 'gerapy --version' or 'pip show gerapy'. If version is below 0.9.9, the system is vulnerable.Check Version:
gerapy --versionVerify Fix Applied:
After upgrading, verify version is 0.9.9 or higher using 'gerapy --version'.📡 Detection & Monitoring
Log Indicators:
- Unusual command execution patterns in Gerapy logs
- Multiple failed authentication attempts followed by successful login
Network Indicators:
- Unexpected outbound connections from Gerapy server
- Suspicious payloads in HTTP requests to Gerapy endpoints
SIEM Query:
source="gerapy.log" AND (command_execution OR os.system OR subprocess)🔗 References
- https://github.com/Gerapy/Gerapy/issues/197
- https://github.com/Gerapy/Gerapy/issues/217
- https://github.com/Gerapy/Gerapy/security/advisories/GHSA-756h-r2c9-qp5j
- https://lgtm.com/projects/g/Gerapy/Gerapy?mode=tree&ruleFocus=1505994646253
- https://securitylab.github.com/advisories/GHSL-2021-076-gerapy/
- https://github.com/Gerapy/Gerapy/issues/197
- https://github.com/Gerapy/Gerapy/issues/217
- https://github.com/Gerapy/Gerapy/security/advisories/GHSA-756h-r2c9-qp5j
- https://lgtm.com/projects/g/Gerapy/Gerapy?mode=tree&ruleFocus=1505994646253
- https://securitylab.github.com/advisories/GHSL-2021-076-gerapy/
