CVE-2025-50944

Executive Summary

CVE-2025-50944 exposes a critical flaw in AVTECH EagleEyes 2.0.0, where the custom X509TrustManager implementation in push.lite.avtech.com.MySSLSocketFactoryNew.checkServerTrusted only validates the certificate's expiration date, completely bypassing TLS chain-of-trust verification. This allows an attacker to perform man-in-the-middle (MITM) attacks by presenting any valid (or self-signed) certificate that has not expired, intercepting all encrypted communications between the EagleEyes client and its servers. The vulnerability is unpatched as of this report, and no public exploit code exists, but the attack vector is straightforward for any adversary with network access.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Network (N) – Exploitable remotely.
• Attack Complexity (AC): Low (L) – No special conditions required.
• Privileges Required (PR): None (N) – No authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – Impact confined to the vulnerable component.
• Confidentiality (C): High (H) – Full disclosure of encrypted data.
• Integrity (I): High (H) – Attacker can inject malicious data.
• Availability (A): None (N) – No impact on availability.

CVSS Score: 9.1 (Critical) – Immediate attention required.

Deep Dive & Mechanics

The vulnerability resides in the checkServerTrusted method of the MySSLSocketFactoryNew class. In standard TLS, the X509TrustManager must verify the entire certificate chain against trusted root CAs, check hostname validity, and ensure no revocation. The flawed implementation reduces this to a single check:

// Vulnerable code snippet (conceptual)
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
    for (X509Certificate cert : chain) {
        cert.checkValidity(); // Only checks expiration date
    }
    // No chain validation, no hostname verification, no CA trust check
}

This means any certificate that is not expired will be accepted. An attacker can generate a self-signed certificate with a future expiration date and present it during the TLS handshake. The EagleEyes client will trust it, allowing the attacker to decrypt, modify, and re-encrypt traffic.

Vulnerable vs. Patched Code

Vulnerable (EagleEyes 2.0.0):

// MySSLSocketFactoryNew.java
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
    // Only checks expiration
    for (X509Certificate cert : chain) {
        cert.checkValidity();
    }
}

Patched (Hypothetical fix):

// MySSLSocketFactoryNew.java (patched)
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
    // Proper chain validation using default trust manager
    TrustManagerFactory tmf = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
    tmf.init((KeyStore) null);
    X509TrustManager defaultTm = (X509TrustManager) tmf.getTrustManagers()[0];
    defaultTm.checkServerTrusted(chain, authType);
}

The patched version delegates to the system's default trust manager, which performs full chain validation, hostname verification, and revocation checks.

Exploitation & Lab Setup

Red Team (Attacker)

Prerequisites:

• Network access between the attacker and the EagleEyes client (e.g., same Wi-Fi, compromised router).
• Ability to intercept traffic (ARP spoofing, rogue access point, etc.).

Steps:

1. Generate a self-signed certificate with a future expiration date:

   openssl req -x509 -newkey rsa:2048 -keyout attacker.key -out attacker.crt -days 365 -nodes -subj "/CN=attacker.com"
   

2. Set up a MITM proxy (e.g., mitmproxy) using the generated certificate:

   mitmproxy --listen-port 8443 --certs *=attacker.crt
   

3. Redirect EagleEyes traffic to the proxy (e.g., ARP spoofing):

   arpspoof -i eth0 -t <target_ip> <gateway_ip>
   

4. All TLS traffic from EagleEyes will be decrypted and visible in the proxy.

Blue Team (Defender)

Detection:

• Monitor for unexpected certificates in TLS handshakes using network monitoring tools.
• Look for connections to IP addresses that do not match the legitimate AVTECH server domains.
• Use the YARA and Sigma rules below to detect the vulnerable code in APK files.

Mitigation:

• Isolate EagleEyes devices on a separate VLAN with strict egress filtering.
• Use a network-based TLS inspection proxy to enforce proper certificate validation.
• Apply vendor patches as soon as they become available.

Indicators of Compromise (IOCs)

• Network: TLS connections to unknown or suspicious IP addresses on port 443 (or custom ports) that do not match AVTECH's known server infrastructure.
• Certificate: Self-signed certificates or certificates from untrusted CAs presented during EagleEyes communication.
• File: Presence of MySSLSocketFactoryNew.class in the EagleEyes APK with the vulnerable checkServerTrusted method.
• Process: Unusual mitmproxy or openssl processes on the network.

Detection Engineering

YARA Rule

rule CVE_2025_50944_EagleEyes_TLS_Bypass {
    meta:
        description = "Detects vulnerable MySSLSocketFactoryNew class in AVTECH EagleEyes 2.0.0"
        author = "Valters IT"
        date = "2025-01-01"
        reference = "CVE-2025-50944"
    strings:
        $class_name = "MySSLSocketFactoryNew"
        $method_name = "checkServerTrusted"
        $vuln_check = "checkValidity"
    condition:
        all of them
}

Sigma Rule

title: CVE-2025-50944 - EagleEyes TLS Certificate Validation Bypass
id: 8a4b3c2d-1e5f-6a7b-8c9d-0e1f2a3b4c5d
status: experimental
description: Detects network traffic from AVTECH EagleEyes devices that may indicate MITM exploitation
author: Valters IT
logsource:
    category: network_connection
    product: windows
detection:
    selection:
        DestinationPort: 443
        Image|endswith: '\EagleEyes.exe'
    condition: selection
falsepositives:
    - Legitimate AVTECH server connections
level: high

Suricata Rule

alert tls $HOME_NET any -> $EXTERNAL_NET 443 (msg:"CVE-2025-50944 - Potential EagleEyes MITM"; flow:to_server; tls.cert_subject:"CN=*"; tls.cert_issuer:"CN=*"; tls.cert_notbefore:"*"; tls.cert_notafter:"*"; reference:cve,2025-50944; classtype:attempted-recon; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate: Isolate all EagleEyes devices on a segmented network with strict firewall rules allowing only necessary outbound connections to known AVTECH servers.
2. Short-term: Deploy a network-based TLS inspection proxy that enforces proper certificate validation for all outbound connections from EagleEyes devices.
3. Long-term: Contact AVTECH for an official patch. If unavailable, consider replacing the device with a vendor that follows secure coding practices.
4. Compensating Controls: Implement host-based intrusion detection (HIDS) on the EagleEyes device (if possible) to monitor for unexpected certificate changes.

Valters IT
Securing Digital Frontiers