CVE-2024-7402

Executive Summary

CVE-2024-7402 describes a security gap in the Netskope Client agent that allows a malicious insider with administrative privileges to perform a Man-in-the-Middle (MITM) attack on the agent’s communication channel. This can lead to temporary alteration of the client configuration or permanent disabling/removal of the agent from the machine. The vulnerability has a CVSS score of 0.0 (unscored) and an EPSS score of 0.0%, indicating low exploitation likelihood at this time. No public proof-of-concept or exploit code is available. The vendor has not released a patch, and the affected version is unknown.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (Unscored)
• Attack Vector (AV): Local (requires administrative privileges)
• Attack Complexity (AC): Low
• Privileges Required (PR): High (administrator)
• User Interaction (UI): None
• Scope (S): Unchanged
• Confidentiality Impact (C): None (configuration tampering)
• Integrity Impact (I): High (agent config altered or agent disabled)
• Availability Impact (A): High (agent can be permanently removed)
• Threat Level: Medium (requires insider access but impact is significant)

Deep Dive & Mechanics

The vulnerability resides in the Netskope Client agent’s communication channel. A malicious insider with administrative rights on the endpoint can intercept and modify traffic between the agent and the Netskope cloud infrastructure. By performing a MITM attack, the attacker can:

• Temporarily alter configuration: Change policy settings, disable security features, or redirect traffic.
• Permanently disable or remove the agent: Uninstall or corrupt the agent, leaving the endpoint unprotected.

The attack requires the attacker to already have administrative privileges, making it a post-exploitation or insider threat scenario. The lack of proper certificate pinning or integrity checks on the agent’s communication channel enables this MITM activity.

Vulnerable vs. Patched Code

No specific code diff is available. The vulnerability is a design flaw in the agent’s communication channel rather than a code-level bug. A patched version would likely implement:

• Certificate pinning to prevent MITM with forged certificates.
• Integrity verification of configuration files and agent binaries.
• Secure boot or tamper-proofing mechanisms to prevent agent removal.

Exploitation & Lab Setup

Red Team

Prerequisites: Administrative privileges on the target Windows/macOS machine.

Steps:

1. Install a MITM proxy (e.g., Burp Suite, mitmproxy) on the target machine.
2. Configure the system to trust a self-signed CA certificate.
3. Intercept traffic from the Netskope Client agent (typically on ports 443 or custom ports).
4. Modify configuration responses to disable security policies or trigger agent uninstall.
5. Alternatively, use a script to kill the agent process and delete its binaries.

Example MITM proxy setup (conceptual):

# Install mitmproxy
pip install mitmproxy

# Run mitmproxy in transparent mode
mitmproxy --mode transparent --listen-port 8080

# Redirect agent traffic using iptables (Linux) or netsh (Windows)

Blue Team

Detection:

• Monitor for unexpected certificate installations (Event ID 6416 on Windows).
• Alert on agent process termination or service stop events.
• Use file integrity monitoring (FIM) on agent binaries and configuration files.
• Enable logging of agent communication endpoints and look for anomalies.

Prevention:

• Enforce least privilege; restrict administrative access.
• Use application whitelisting to prevent unauthorized MITM tools.
• Deploy endpoint detection and response (EDR) with behavioral analytics.

Indicators of Compromise (IOCs)

• Network: Unusual TLS handshakes with self-signed certificates on Netskope agent ports.
• Process: Suspicious processes (e.g., mitmproxy, Burp Suite) running on endpoints.
• File: Modified Netskope configuration files (e.g., netskope.conf, agent.cfg).
• Registry (Windows): Changes to HKLM\SOFTWARE\Netskope\Client keys.
• Service: Netskope Client service (NetskopeClient) stopped or disabled.

Detection Engineering

YARA Rule

rule CVE_2024_7402_Netskope_MITM {
    meta:
        description = "Detects potential MITM tools or tampered Netskope agent files"
        author = "Valters IT"
        date = "2025-04-10"
        reference = "CVE-2024-7402"
    strings:
        $s1 = "mitmproxy" nocase
        $s2 = "burpsuite" nocase
        $s3 = "netskope" nocase
        $s4 = "agent.cfg" nocase
    condition:
        any of ($s1, $s2) or ($s3 and $s4)
}

Sigma Rule

title: Netskope Agent Configuration Tampering
id: 7a8b9c0d-1e2f-3a4b-5c6d-7e8f9a0b1c2d
status: experimental
description: Detects potential MITM activity targeting Netskope Client agent
author: Valters IT
date: 2025-04-10
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\\mitmproxy.exe'
            - '\\burpsuite.exe'
            - '\\fiddler.exe'
    condition: selection
falsepositives:
    - Legitimate use of MITM tools by authorized personnel
level: high

Suricata Rule

alert tls $HOME_NET any -> $EXTERNAL_NET 443 (
    msg:"CVE-2024-7402 - Potential MITM on Netskope Agent";
    flow:to_server;
    tls.cert_subject:"CN=*";
    tls.cert_issuer:"CN=*";
    tls.cert_notbefore:"2025-01-01";
    tls.cert_notafter:"2026-01-01";
    sid:1000001;
    rev:1;
)

Remediation & Mitigation

1. Immediate: Restrict administrative privileges to only trusted personnel.
2. Short-term: Monitor for unauthorized certificate installations and agent tampering.
3. Long-term: Apply vendor patch when available. Implement certificate pinning and agent integrity checks.
4. Compensating controls: Use EDR to detect and block MITM tools. Enable Windows Defender Application Control (WDAC) or similar.

Valters IT
DevSecOps & Cyber Threat Intelligence Expert