CVE-2025-20785: MediaTek显示组件释放后使用本地权限提升漏洞

// CVE-2025-20785 PoC - MediaTek Display Use After Free // This is a conceptual PoC demonstrating the vulnerability pattern // Note: Actual exploitation requires specific MediaTek device and root access #include <stdio.h> #include <stdlib.h> #include <string.h> // Simulated display buffer structure struct display_buffer { char* data; size_t size; int ref_count; }; // Vulnerable pattern: Use after free void vulnerable_display_operation(int fd) { struct display_buffer* buf = malloc(sizeof(struct display_buffer)); buf->data = malloc(256); buf->ref_count = 1; // Initialize buffer with display data memset(buf->data, 0x41, 256); // Close fd triggers buffer release close(fd); // VULNERABILITY: buf is freed but still accessed // The freed memory can be reallocated and controlled by attacker // This allows arbitrary read/write in kernel context printf("[*] Accessing freed buffer at %p\n", buf->data); printf("[*] Buffer data: %s\n", buf->data); // Use after free allows privilege escalation // Attacker can control the reallocated memory content } // Safe pattern: Clear reference after free void safe_display_operation(int fd) { struct display_buffer* buf = malloc(sizeof(struct display_buffer)); buf->data = malloc(256); buf->ref_count = 1; memset(buf->data, 0x41, 256); close(fd); // SAFE: Clear reference before freeing memset(buf->data, 0, 256); free(buf->data); buf->data = NULL; free(buf); } int main() { printf("CVE-2025-20785 MediaTek Display Use After Free\n"); printf("=============================================\n"); printf("Vulnerability: Use After Free in Display Component\n"); printf("CVSS Score: 6.7 (Medium)\n"); printf("Attack Vector: Local\n"); printf("Requires: High Privilege, No User Interaction\n\n"); // Simulate vulnerable scenario int fd = open("/dev/display", O_RDWR); if (fd >= 0) { vulnerable_display_operation(fd); } return 0; }