The Real-World Cost of Misconfigured VPNs and Cleartext Credentials

TLDR: The Black Hat Asia 2024 NOC report reveals that even in a room full of security professionals, basic hygiene failures like split-tunneling and cleartext credential leakage remain rampant. Attackers are actively exploiting these misconfigurations to gain unauthorized access to critical infrastructure. Pentesters should prioritize testing for these "low-hanging" fruits during engagements, as they consistently yield high-impact results.

Security conferences are supposed to be the safest places on the planet for network traffic, yet the reality inside the Black Hat Asia 2024 Network Operations Center (NOC) tells a different story. When you put thousands of security researchers, pentesters, and developers in one room, you don't get a hardened, impenetrable fortress. You get a microcosm of the real world, complete with every bad habit, misconfiguration, and oversight that plagues corporate environments globally. The NOC team’s retrospective analysis of their traffic logs proves that even experts fall victim to the same fundamental flaws they spend their days trying to patch.

The Persistence of Basic Hygiene Failures

The most striking takeaway from the NOC report is the sheer volume of traffic that shouldn't exist in a professional environment. We are talking about massive amounts of cleartext data being broadcast over the network. Despite years of industry advocacy for Zero Trust principles, the data shows that users are still relying on broken authentication mechanisms and insecure protocols.

One of the most common offenders is the misconfigured VPN. Many users believe that simply connecting to a VPN provides a blanket of security, but the NOC logs show a different reality. Split-tunneling is the primary culprit. When a user enables split-tunneling, they are essentially creating a bridge between a secure corporate environment and the wild, untrusted internet. If that tunnel isn't configured with strict routing rules, sensitive traffic leaks into the clear. We saw instances where internal traffic, including authentication tokens and cleartext credentials, was being routed outside the encrypted tunnel, making it trivial for an attacker on the same local network to intercept.

Exploiting the "Low-Hanging" Fruit

During the conference, the NOC team observed active attempts to exploit CVE-2024-3400, a critical command injection vulnerability in Palo Alto Networks' GlobalProtect gateway. This is a perfect example of why patching and configuration management are non-negotiable. When a vulnerability like this hits the wild, it doesn't wait for a convenient time to be exploited. It is weaponized almost immediately.

For a pentester, this is a reminder that you don't always need a zero-day to compromise a target. You need to look for the gaps in the implementation. If you are performing an external assessment, your first step should always be to map the attack surface for these known, high-impact vulnerabilities. If you find a gateway that hasn't been patched or is running a vulnerable version of the software, you have a clear path to execution.

The NOC team also highlighted the prevalence of cleartext credentials being sent over the wire. This is often the result of legacy applications or poorly written scripts that haven't been updated to use modern, secure transport layers. When you see a developer or researcher hardcoding credentials into a script or using basic authentication over HTTP, you are looking at a potential entry point for an attacker.

The Role of Automated Threat Intelligence

Monitoring a network of this scale requires more than just manual log analysis. The NOC team relied heavily on Corelight and NetWitness to ingest and analyze traffic in real-time. The goal is to move from reactive alerting to proactive hunting. By correlating network telemetry with threat intelligence feeds, the team could identify malicious patterns—like a device beaconing to a known command-and-control server—before the attacker could establish a foothold.

For those of you running red team engagements, this is the environment you are up against. The days of simply running a scanner and hoping for the best are over. Modern blue teams are using automated tools to detect anomalous behavior at the network layer. If you want to succeed, you need to understand how your traffic looks to these sensors. You need to be able to blend in with the noise.

What This Means for Your Next Engagement

The lessons from the Black Hat Asia NOC are clear: the most dangerous threats are often the ones we ignore because they seem too basic. We spend so much time focusing on complex exploit chains and advanced persistent threats that we forget to check if our VPN is leaking traffic or if our applications are still using base64-encoded "authentication" that anyone can decode.

If you are a pentester, use this as a checklist for your next engagement. Don't just look for the shiny new vulnerabilities. Look for the split-tunneling configurations, the cleartext credentials, and the outdated protocols. These are the vulnerabilities that get exploited in the real world every single day. If you can find them, you can help your clients build a more resilient infrastructure. And if you are a defender, take a hard look at your network logs. If you aren't seeing this kind of traffic, you probably aren't looking hard enough. The data is there, and it’s telling a story—make sure you’re the one reading it.