CVE-2024-52330

Executive Summary

CVE-2024-52330 exposes a critical flaw in Ecovacs lawnmowers and vacuums where TLS certificate validation is improperly implemented. An unauthenticated, remote attacker can intercept, read, or modify TLS traffic, including firmware updates. This allows for man-in-the-middle (MITM) attacks, potential device compromise, and persistent backdoor installation. The vulnerability affects all devices that rely on Ecovacs cloud services for firmware delivery and telemetry. No patch is currently available, and no public exploit code has been released.

CVSS Breakdown & Threat Level

• CVSS Score: 7.4 (High)
• Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High
• EPSS Score: 0.0% (low exploitation probability currently)
• Threat Level: High – due to ease of exploitation and potential for full device takeover.

Deep Dive & Mechanics

The vulnerability lies in the TLS certificate validation routine within the Ecovacs device firmware. When the device connects to Ecovacs cloud servers for firmware updates or telemetry, it fails to properly verify the server’s TLS certificate. This means an attacker on the same network (or able to perform DNS spoofing) can present a self-signed or otherwise invalid certificate, and the device will accept it.

Attack Flow:

1. Attacker gains a position on the network (e.g., via compromised Wi-Fi, ARP spoofing, or rogue access point).
2. Attacker performs a MITM attack between the Ecovacs device and the legitimate cloud server.
3. Attacker presents a fraudulent TLS certificate; the device does not reject it.
4. Attacker can decrypt, read, and modify all TLS traffic, including firmware update payloads.
5. Attacker can inject malicious firmware, exfiltrate data, or issue commands to the device.

Impact:

• Full device compromise (lawnmower or vacuum).
• Persistent backdoor via modified firmware.
• Potential lateral movement within the home network.
• Privacy breach (device telemetry, camera feeds if present).

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# Vulnerable TLS validation - no certificate check
import ssl
import socket

def connect_to_cloud():
    context = ssl.create_default_context()
    context.check_hostname = False
    context.verify_mode = ssl.CERT_NONE  # No verification
    sock = socket.socket()
    secure_sock = context.wrap_socket(sock, server_hostname="api.ecovacs.com")
    return secure_sock

Patched Code (Conceptual):

# Patched TLS validation - proper certificate check
import ssl
import socket

def connect_to_cloud():
    context = ssl.create_default_context()
    context.check_hostname = True
    context.verify_mode = ssl.CERT_REQUIRED  # Verify certificate
    context.load_verify_locations("/etc/ssl/certs/ca-certificates.crt")
    sock = socket.socket()
    secure_sock = context.wrap_socket(sock, server_hostname="api.ecovacs.com")
    return secure_sock

Exploitation & Lab Setup

Red Team (Attack Simulation)

Prerequisites:

• Kali Linux or similar.
• Bettercap, mitmproxy, or custom Python script.
• Ability to perform ARP spoofing or DNS spoofing on the target network.

Steps:

1. Set up a rogue TLS server with a self-signed certificate.
2. Use ARP spoofing to redirect device traffic to your machine.
3. Intercept and modify firmware update requests.

Example mitmproxy script:

# mitmproxy inline script to intercept Ecovacs firmware updates
from mitmproxy import http

def request(flow: http.HTTPFlow) -> None:
    if "firmware.ecovacs.com" in flow.request.pretty_host:
        print(f"[*] Intercepted firmware request: {flow.request.url}")
        # Optionally modify the response later

def response(flow: http.HTTPFlow) -> None:
    if "firmware.ecovacs.com" in flow.request.pretty_host:
        print(f"[*] Firmware response intercepted, size: {len(flow.response.content)}")
        # Inject malicious payload here
        # flow.response.content = malicious_firmware

Usage: Run mitmproxy -s script.py --mode transparent and configure iptables to redirect traffic.

Blue Team (Detection & Defense)

Detection:

• Monitor for unexpected TLS certificate changes or self-signed certificates on the network.
• Use network anomaly detection for unusual firmware update patterns.
• Deploy a TLS inspection proxy to validate all outbound TLS connections.

Defense:

• Isolate IoT devices on a separate VLAN with strict egress filtering.
• Disable automatic firmware updates until a patch is available.
• Use a VPN or secure tunnel for all device communications.

Indicators of Compromise (IOCs)

• Network:
  • TLS connections to Ecovacs servers using self-signed or untrusted certificates.
  • Unusual DNS queries for firmware.ecovacs.com or api.ecovacs.com from unexpected IPs.
  • ARP spoofing alerts on the local network.
• Host (Device):
  • Modified firmware hash (compare against known good hash).
  • Unexpected open ports or processes on the device.
  • Unusual outbound connections to unknown IPs.
• File:
  • Suspicious firmware update files with invalid signatures.

Detection Engineering

YARA Rule

rule CVE_2024_52330_Ecovacs_TLS_Bypass {
    meta:
        description = "Detects Ecovacs firmware with disabled TLS certificate validation"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-52330"
    strings:
        $s1 = "CERT_NONE" ascii wide nocase
        $s2 = "check_hostname = False" ascii wide nocase
        $s3 = "verify_mode = ssl.CERT_NONE" ascii wide nocase
    condition:
        any of ($s*)
}

Sigma Rule

title: Ecovacs TLS Certificate Validation Disabled
id: 8f7a3b2c-1d4e-5f6a-7b8c-9d0e1f2a3b4c
status: experimental
description: Detects network traffic indicating Ecovacs devices accepting invalid TLS certificates
author: Valters IT
date: 2025-04-10
references:
    - CVE-2024-52330
logsource:
    category: network_connection
    product: zeek
detection:
    selection:
        server_name: "api.ecovacs.com" or "firmware.ecovacs.com"
        certificate_validation: "self-signed" or "invalid"
    condition: selection
falsepositives:
    - Legitimate testing environments
level: high

Suricata Rule

alert tls $HOME_NET any -> $EXTERNAL_NET 443 (msg:"CVE-2024-52330 Ecovacs TLS Certificate Validation Bypass"; flow:to_server; tls.cert_issuer:!".*Ecovacs.*"; tls.cert_subject:!".*Ecovacs.*"; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Isolate devices: Place Ecovacs devices on a separate VLAN with no direct internet access.
2. Disable auto-update: Turn off automatic firmware updates in the Ecovacs app.
3. Monitor network: Use IDS/IPS rules (above) to detect exploitation attempts.
4. Contact vendor: Pressure Ecovacs to release a firmware patch that implements proper TLS certificate validation.

Long-term Fix:

• Vendor must update firmware to use certificate pinning or proper CA validation.
• Users should only download firmware from official sources and verify checksums.

Workaround:

• Use a VPN router to tunnel all IoT traffic through a secure endpoint that performs TLS inspection.

Valters IT