CVE-2025-66963

Executive Summary

CVE-2025-66963 identifies a local information disclosure vulnerability in the Hitron HI3120 router running firmware version 7.2.4.5.2b1. The flaw resides in the Logout option within index.html, which exposes sensitive information to a local attacker. This vulnerability has a CVSS score of 0.0 (likely unassigned or placeholder), but the exposure of sensitive data could facilitate further attacks against the device or network. No public exploit code or patch is currently available.

Supply Chain & Package Security

This vulnerability is not related to NPM, PyPI, Go, or Ruby packages. It is a firmware-level issue in a consumer networking device.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (Unassigned / Placeholder)
• Attack Vector: Local (AV:L)
• Attack Complexity: Low (AC:L)
• Privileges Required: Low (PR:L)
• User Interaction: None (UI:N)
• Scope: Unchanged (S:U)
• Confidentiality Impact: High (C:H)
• Integrity Impact: None (I:N)
• Availability Impact: None (A:N)
• Threat Level: Medium (due to local access requirement but high confidentiality impact)

Deep Dive & Mechanics

The vulnerability is triggered when a local attacker interacts with the Logout option in the web interface (index.html). The exact mechanism is not publicly detailed, but it likely involves the improper handling of session data or credentials during the logout process. Instead of securely clearing sensitive information, the device may expose it in the response or leave it accessible in a way that can be captured by a local attacker.

The attack requires local access to the device's network or physical console. Once the attacker triggers the logout, they can intercept or read sensitive data such as session tokens, configuration details, or credentials.

Vulnerable vs. Patched Code

No patch is currently available. The vulnerable code is in the firmware version 7.2.4.5.2b1. A patched version would need to ensure that the logout process securely clears all sensitive data and does not expose it in any response or log.

Exploitation & Lab Setup

Red Team

1. Setup: Obtain a Hitron HI3120 router with firmware version 7.2.4.5.2b1. Connect to the device's local network.
2. Access: Open a web browser and navigate to the router's web interface (e.g., http://192.168.1.1).
3. Trigger: Log in with valid credentials, then click the Logout option.
4. Capture: Use a tool like Burp Suite or Wireshark to capture the HTTP response after logout. Look for sensitive data in the response body or headers.
5. Exploit: If sensitive data is found, use it for further attacks (e.g., session hijacking, credential reuse).

Blue Team

1. Detection: Monitor for unusual HTTP requests to the logout endpoint. Look for patterns where a user logs out and immediately makes a request to capture data.
2. Mitigation: Restrict local access to the router's web interface. Use network segmentation to limit who can reach the device.
3. Hardening: Disable remote management and change default credentials. Apply any firmware updates as soon as they become available.

Indicators of Compromise (IOCs)

• Network: HTTP requests to /index.html with a logout parameter.
• Logs: Router logs showing repeated logout actions from the same IP.
• File: Presence of temporary files or cookies containing sensitive data after logout.

Detection Engineering

YARA Rule

rule CVE_2025_66963_Hitron_Logout_InfoDisclosure {
    meta:
        description = "Detects sensitive data exposure in Hitron HI3120 logout response"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2025-66963"
    strings:
        $sensitive1 = "password" ascii wide nocase
        $sensitive2 = "session" ascii wide nocase
        $sensitive3 = "token" ascii wide nocase
        $logout = "logout" ascii wide nocase
    condition:
        $logout and (any of ($sensitive*))
}

Sigma Rule

title: Hitron HI3120 Logout Information Disclosure
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects potential exploitation of CVE-2025-66963 via logout response
author: Valters IT
date: 2025-04-10
logsource:
    category: webserver
    product: hitron
detection:
    selection:
        cs-method: GET
        cs-uri-stem: /index.html
        cs-uri-query: '*logout*'
    condition: selection
falsepositives:
    - Legitimate logout actions
level: medium

Suricata Rule

alert http any any -> any any (msg:"CVE-2025-66963 Hitron HI3120 Logout Info Disclosure"; flow:to_server; content:"GET"; http_method; content:"/index.html"; http_uri; content:"logout"; http_uri; sid:1000001; rev:1;)

Remediation & Mitigation

• Immediate: Restrict local access to the router's web interface. Use strong, unique passwords and disable remote management.
• Short-term: Monitor for firmware updates from Hitron. Apply patches as soon as they are released.
• Long-term: Replace the device with a more secure alternative if no patch is provided. Implement network segmentation to isolate vulnerable devices.

Valters IT signature: This report is generated for educational and defensive purposes. All information is based on publicly available data and should be verified before action.