CVE-2025-65825

Executive Summary

CVE-2025-65825 exposes a critical hardware-level vulnerability in the Meatmeet basestation firmware. The firmware is stored unencrypted on the device, allowing an attacker with physical access to disassemble the device, connect over UART, and dump the firmware. Within the NVS (Non-Volatile Storage) partition, credentials for current and previous Wi-Fi networks are stored in plaintext. This enables an adversary to retrieve Wi-Fi passwords and gain unauthorized access to the victim’s network, potentially leading to lateral movement, data exfiltration, or further compromise.

This vulnerability is particularly dangerous because it requires no authentication or network access—only physical possession of the device. The lack of encryption and absence of a vendor patch make it a high-risk issue for users of Meatmeet products.

Supply Chain & Package Security

This vulnerability is not related to any software package manager (NPM, PyPI, Go, Ruby). It is a hardware/firmware issue specific to the Meatmeet basestation.

CVSS Breakdown & Threat Level

While no official CVSS vector is provided, a reasonable assessment based on the description is:

• Attack Vector (AV): Physical (P) – Requires physical access to the device.
• Attack Complexity (AC): Low (L) – Disassembly and UART connection are straightforward.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Changed (C) – Compromise of the device leads to network access.
• Confidentiality (C): High (H) – Wi-Fi credentials are exposed.
• Integrity (I): None (N) – No data modification.
• Availability (A): None (N) – No denial of service.

Estimated CVSS Score: 6.8 (Medium) – Physical access required, but impact is significant.

Threat Level: High for environments where physical security is weak (e.g., public kiosks, shared offices, or unattended devices).

Deep Dive & Mechanics

The vulnerability stems from the lack of firmware encryption on the Meatmeet basestation. The device stores Wi-Fi credentials in an NVS partition without any obfuscation or encryption. An attacker can:

1. Gain Physical Access: Obtain the device (e.g., from a trash bin, unattended desk, or via theft).
2. Disassemble: Open the casing to access the PCB.
3. Connect over UART: Identify UART pins (TX, RX, GND) and connect a USB-to-UART adapter (e.g., FTDI) to a computer.
4. Dump Firmware: Use tools like esptool.py (for ESP32-based devices) or flashrom to read the flash memory.
5. Extract NVS Partition: Parse the NVS partition using nvs_flash utilities or hex editors to find Wi-Fi SSID and password strings.

The credentials are stored in plaintext, allowing the attacker to connect to the victim’s Wi-Fi network and potentially pivot to other devices.

Vulnerable vs. Patched Code

Vulnerable Code (Firmware):
The firmware stores Wi-Fi credentials in NVS without encryption. Example pseudocode:

nvs_handle_t nvs_handle;
nvs_open("storage", NVS_READWRITE, &nvs_handle);
nvs_set_str(nvs_handle, "wifi_ssid", "MyNetwork");
nvs_set_str(nvs_handle, "wifi_password", "secret123");
nvs_commit(nvs_handle);

Patched Code (Hypothetical):
Credentials should be encrypted before storage. Example using AES:

#include "mbedtls/aes.h"
// Encrypt password before storing
nvs_set_blob(nvs_handle, "wifi_password_enc", encrypted_data, encrypted_len);

No official patch exists; this is a recommended fix.

Exploitation & Lab Setup

Red Team (Attacker)

Lab Setup:

• Meatmeet basestation (vulnerable firmware)
• USB-to-UART adapter (e.g., FT232RL)
• Computer with Python and esptool.py
• Screwdrivers, multimeter

Steps:

1. Disassemble the device to expose the PCB.
2. Identify UART pins (TX, RX, GND) using a multimeter or datasheet.
3. Connect UART adapter: TX->RX, RX->TX, GND->GND.
4. Open a serial terminal (e.g., screen /dev/ttyUSB0 115200).
5. Interrupt boot (if needed) to access firmware dump.
6. Use esptool.py --port /dev/ttyUSB0 read_flash 0x0 0x400000 firmware.bin to dump 4MB flash.
7. Extract NVS partition: python nvs_parser.py firmware.bin (custom script).
8. Parse output to retrieve Wi-Fi SSID and password.

Example Command:

esptool.py --port /dev/ttyUSB0 read_flash 0x9000 0x6000 nvs.bin
strings nvs.bin | grep -E "^(ssid|password)"

Blue Team (Defender)

Detection & Response:

• Monitor for physical tampering (e.g., casing opened, UART activity).
• Use network monitoring to detect new devices connecting to Wi-Fi with stolen credentials.
• Implement credential rotation and use WPA2-Enterprise with 802.1X to limit exposure.
• Deploy endpoint detection on devices that connect to the same network.

Mitigation:

• Physically secure the Meatmeet device (e.g., locked enclosure).
• Apply firmware updates if vendor releases a patch.
• Use a separate IoT VLAN to isolate the device.

Indicators of Compromise (IOCs)

• Network: Unauthorized device connecting to the victim’s Wi-Fi network with known SSID.
• Physical: Signs of tampering (scratches, opened casing, loose screws).
• Firmware: Dumped firmware file (e.g., firmware.bin) on attacker’s system.
• UART: Serial traffic on unknown UART pins (detectable with oscilloscope).

Detection Engineering

YARA Rule

rule Meatmeet_Firmware_Credentials {
    meta:
        description = "Detects plaintext Wi-Fi credentials in Meatmeet firmware dump"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-65825"
    strings:
        $ssid = /wifi_ssid\x00[a-zA-Z0-9_\-\.]+/
        $password = /wifi_password\x00[a-zA-Z0-9_\-\.!@#$%^&*()]+/
    condition:
        any of them
}

Sigma Rule

title: Meatmeet Firmware Credential Extraction
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects attempts to dump firmware via UART on Meatmeet devices
logsource:
    product: linux
    service: syslog
detection:
    selection:
        - "esptool.py" or "flashrom" or "UART" or "serial"
    condition: selection
falsepositives:
    - Legitimate firmware updates
level: high

Suricata Rule

alert tcp any any -> any any (msg:"Meatmeet Firmware Dump via UART"; content:"esptool.py"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Physically secure the Meatmeet device (e.g., locked cabinet, tamper-evident seals).
2. Change Wi-Fi credentials immediately if device was compromised.
3. Isolate the device on a separate VLAN with limited network access.

Long-Term Fixes:

• Vendor must release firmware with encrypted NVS storage.
• Implement secure boot and flash encryption (e.g., ESP32 flash encryption).
• Use hardware security modules (HSM) for credential storage.

Workarounds:

• Disable Wi-Fi on the device if not needed.
• Use a separate IoT network with strong access controls.

Valters IT
DevSecOps & Cyber Threat Intelligence Expert