CVE-2024-12079

Executive Summary

CVE-2024-12079 exposes a critical security flaw in ECOVACS robotic lawnmowers, where the anti-theft PIN is stored in cleartext on the device’s filesystem. This vulnerability allows an attacker with physical access to the device to extract the PIN, bypass the anti-theft mechanism, and effectively steal the lawnmower without triggering any alarms. The vulnerability is classified under CWE-312 (Cleartext Storage of Sensitive Information) and is currently unpatched by the vendor. The attack vector is physical, requiring the attacker to possess the device, but the impact is high as it compromises the device’s primary security control.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a hardware/firmware issue specific to ECOVACS robotic lawnmowers.

CVSS Breakdown & Threat Level

• CVSS Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Base Score: 6.6 (Medium)
• Attack Vector (AV): Physical (P) – The attacker must have physical access to the device.
• Attack Complexity (AC): Low (L) – No special conditions or mitigations are required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerability does not affect other components.
• Confidentiality (C): High (H) – The PIN is fully exposed.
• Integrity (I): High (H) – The attacker can reset the anti-theft mechanism.
• Availability (A): High (H) – The device can be stolen and reused.

Threat Level: Medium. While the CVSS score is moderate, the real-world impact is significant for device owners, as it undermines the core security feature of the product.

Deep Dive & Mechanics

The vulnerability resides in the firmware of ECOVACS robotic lawnmowers. The anti-theft PIN, intended to prevent unauthorized use after theft, is stored in cleartext within a configuration file on the device’s filesystem. An attacker with physical access can connect to the device’s internal storage (e.g., via UART, JTAG, or by removing the SD card if present) and read the PIN directly.

Technical Details:

• The PIN is likely stored in a file such as /config/antitheft.conf or similar.
• No encryption or hashing is applied to the PIN value.
• The attacker can then use the PIN to disable the anti-theft feature, reset the device, and operate it as their own.

Attack Flow:

1. Attacker physically steals the lawnmower.
2. Attacker accesses the device’s filesystem (e.g., via serial console or by removing storage).
3. Attacker reads the cleartext PIN from the configuration file.
4. Attacker uses the PIN to disable the anti-theft mechanism.
5. Attacker resets the device and uses it normally.

Vulnerable vs. Patched Code

Since no patch is available, we can only describe the vulnerable state.

Vulnerable Code (Conceptual):

// Example of vulnerable PIN storage
void store_pin(char *pin) {
    FILE *fp = fopen("/config/antitheft.conf", "w");
    fprintf(fp, "PIN=%s", pin);  // Stored in cleartext
    fclose(fp);
}

Patched Code (Hypothetical):

// Example of secure PIN storage
void store_pin(char *pin) {
    char hashed_pin[64];
    sha256_hash(pin, hashed_pin);  // Hash the PIN
    FILE *fp = fopen("/config/antitheft.conf", "w");
    fprintf(fp, "PIN_HASH=%s", hashed_pin);  // Store hash only
    fclose(fp);
}

Exploitation & Lab Setup

Red Team (Exploitation)

Prerequisites:

• Physical access to an ECOVACS robotic lawnmower.
• Basic tools: screwdriver, USB-to-serial adapter, or SD card reader.

Steps:

1. Disassemble the lawnmower to access the main circuit board.
2. Identify the UART pins or remove the SD card (if present).
3. Connect to the serial console using a USB-to-serial adapter (e.g., at 115200 baud).
4. Boot the device and interrupt the bootloader to get a shell.
5. Navigate to the filesystem and locate the configuration file:

   cat /config/antitheft.conf
   

6. Extract the PIN from the output (e.g., PIN=1234).
7. Use the PIN to disable the anti-theft feature via the device’s interface.

Example Output:

# cat /config/antitheft.conf
PIN=1234

Blue Team (Defense & Detection)

Defensive Measures:

• Physical Security: Secure the lawnmower in a locked shed or garage.
• Firmware Updates: Monitor ECOVACS for any future patches.
• Tamper Detection: Add a third-party GPS tracker or alarm to the device.
• Network Monitoring: If the device connects to Wi-Fi, monitor for unusual traffic (e.g., attempts to exfiltrate data).

Detection Rules:

• Monitor for physical access attempts (e.g., vibration sensors).
• Log any serial console activity if accessible.

Indicators of Compromise (IOCs)

• File Path: /config/antitheft.conf (or similar)
• File Content Pattern: PIN=[0-9]{4,8} (cleartext numeric PIN)
• Physical Indicators: Signs of tampering (e.g., opened casing, disconnected wires)
• Network Indicators: Unusual outbound connections from the lawnmower (if Wi-Fi enabled)

Detection Engineering

YARA Rule

rule ecovacs_cleartext_pin {
    meta:
        description = "Detects cleartext PIN storage in ECOVACS lawnmower config files"
        author = "Valters IT"
        date = "2024-12-01"
        reference = "CVE-2024-12079"
    strings:
        $pin_pattern = /PIN=[0-9]{4,8}/
    condition:
        $pin_pattern
}

Sigma Rule

title: ECOVACS Lawnmower Cleartext PIN Storage
id: 8a9b7c6d-5e4f-3a2b-1c0d-9e8f7a6b5c4d
status: experimental
description: Detects cleartext PIN storage in ECOVACS lawnmower configuration files
author: Valters IT
date: 2024-12-01
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2024-12079
logsource:
    category: file_event
    product: linux
detection:
    selection:
        TargetFilename|contains: 'antitheft.conf'
        TargetFilename|endswith: '.conf'
    condition: selection
falsepositives:
    - Unknown
level: high

Suricata Rule

alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ECOVACS Lawnmower Potential Data Exfiltration"; flow:to_server; content:"antitheft"; nocase; content:"PIN"; nocase; distance:0; within:100; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Physical Security: Store the lawnmower in a secure, locked location.
2. Disable Wi-Fi: If not needed, disable the lawnmower’s Wi-Fi to reduce attack surface.
3. Monitor for Updates: Regularly check ECOVACS’s website for firmware updates.

Long-Term Fixes (Vendor):

• Encrypt or hash the PIN before storage.
• Use hardware security modules (HSM) or secure enclaves for sensitive data.
• Implement tamper-proof storage (e.g., eFuse).

Workarounds:

• Third-party GPS tracker: Attach a hidden GPS tracker to recover the device if stolen.
• Insurance: Ensure the lawnmower is covered under home insurance.

Valters IT
DevSecOps & Cyber Threat Intelligence Expert