CVE-2022-27262
📋 TL;DR
CVE-2022-27262 is a critical arbitrary file upload vulnerability in Skipper v0.9.1 that allows attackers to upload malicious files and execute arbitrary code on affected systems. This affects all deployments running the vulnerable version of Skipper's file upload module. Attackers can achieve remote code execution without authentication.
💻 Affected Systems
- Skipper
📦 What is this software?
Skipper by Sailsjs
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control over the server, data exfiltration, lateral movement, and persistent backdoor installation.
Likely Case
Remote code execution leading to web shell deployment, data theft, and potential ransomware deployment.
If Mitigated
File uploads blocked or properly validated, limiting impact to denial of service or failed upload attempts.
🎯 Exploit Status
Exploitation requires only a crafted file upload request. Public proof-of-concept exists in video references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: http://skipper.com
Restart Required: Yes
Instructions:
1. Check vendor website for updated version. 2. Backup configuration. 3. Deploy updated version. 4. Restart Skipper service.
🔧 Temporary Workarounds
Disable file upload module
allTemporarily disable the vulnerable file upload functionality
# Edit Skipper configuration to disable file upload module
# Restart Skipper service
Implement WAF rules
allBlock malicious file upload patterns at web application firewall
# Configure WAF to block file uploads to vulnerable endpoints
# Implement file type validation rules
🧯 If You Can't Patch
- Implement strict file type validation and size limits
- Deploy network segmentation and isolate Skipper instances
🔍 How to Verify
Check if Vulnerable:
Check Skipper version and verify file upload functionality existsCheck Version:
skipper --versionVerify Fix Applied:
Test file upload with malicious payloads to confirm blocking📡 Detection & Monitoring
Log Indicators:
- Unusual file upload patterns
- Executable file uploads
- Large file uploads to upload endpoints
Network Indicators:
- POST requests to file upload endpoints with executable extensions
- Unusual outbound connections after upload
SIEM Query:
source="skipper.log" AND ("upload" OR "file") AND ("php" OR "exe" OR "jsp" OR "war")