CVE-2026-33983 FreeRDP拒绝服务漏洞

#include <stdio.h> #include <stdint.h> // PoC Code snippet simulating the logic of CVE-2026-33983 // This simulates the behavior in progressive_decompress_tile_upgrade // Mock function to simulate the mismatch detection int progressive_rfx_quant_cmp_equal_mock() { // Returns 0 to simulate a detected mismatch return 0; } void vulnerable_function_simulation() { printf("[VULNERABLE FUNCTION START]\n"); // Step 1: Check for mismatch (simulating progressive_rfx_quant_cmp_equal) if (!progressive_rfx_quant_cmp_equal_mock()) { // Vulnerability: Code only logs a warning but continues execution printf("WLog_WARN: Quantization mismatch detected, but continuing...\n"); } // Step 2: Execution continues with the wrapped value // In the real vulnerability, a value of 247 is used as a shift exponent uint32_t wrapped_value = 247; uint32_t base = 1; printf("Attempting shift operation with exponent: %u\n", wrapped_value); // Step 3: Undefined Behavior / Massive Loop trigger // Note: '1 << 247' is undefined behavior in C for 32-bit integers. // In the actual FreeRDP code, this leads to a loop condition causing ~80 billion iterations. // We simulate the impact description here. // To avoid hanging the system during this demonstration, we comment out the actual UB line. // uint32_t result = base << wrapped_value; printf("[IMPACT] This would trigger a loop of ~80 billion iterations (CPU DoS).\n"); printf("[VULNERABLE FUNCTION END]\n"); } int main() { vulnerable_function_simulation(); return 0; }