[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$flUh_7o_RmSN6ZBojPUlWn2Ov5VqQ4cwPdpc2pRdXanU":3},{"article":4,"iocs":44},{"id":5,"title":6,"slug":7,"summary":8,"ai_summary":9,"brief":10,"full_text":11,"url":12,"image_url":13,"published_at":14,"ingested_at":15,"relevance_score":16,"entities":17,"category_id":21,"category":22,"article_tags":26},"253c9f81-4da6-4a96-9204-6d409c4c3b67","Named Pipes Under Attack: Securing Windows Interprocess Communication","named-pipes-under-attack-securing-windows-interprocess-communication-018a1d","Windows named pipes provide fast interprocess communication, but weak access controls can expose privileged services to untrusted processes. ThreatLocker explains how endpoint verification, command authorization, strict input validation, and narrowly scoped privileges can help secure named-pipe communication. [...]","Windows named pipes, often treated as trusted internal communication channels, are vulnerable to exploitation due to weak access controls. ThreatLocker highlights that any process with sufficient access rights can connect to a named pipe, potentially exposing privileged services to untrusted applications or malware. The article emphasizes the need for robust security measures, including endpoint verification, command authorization, strict input validation, and narrowly scoped privileges, to protect these communication channels.","Windows named pipes can be exploited due to weak access controls, exposing privileged services.","Named Pipes Under Attack: Securing Windows Interprocess Communication Sponsored by ThreatLocker August 22, 2026 09:00 AM 0 Written by: Farid Mustafayev, Cybersecurity Expert at ThreatLocker Named pipes are a common choice for communication between applications running on the same Windows computer. They are fast, supported directly by the operating system, and work well for communication between Windows services, desktop applications, tray processes, command-line utilities, and background agents. A typical design may include a privileged Windows service acting as the named-pipe server while a user-facing application connects as the client. Because both processes run on the same computer, developers often treat this communication as internal and therefore trusted. In practice, the pipe is accessible from an environment where many unrelated processes may be running under different users, sessions, and security contexts. Local Does Not Mean Trusted Named pipes are often treated as private because they are used for communication between applications on the same computer. That assumption is unsafe. A Windows workstation may run processes under LocalSystem, administrators, standard users, service accounts, and separate interactive or remote sessions. It may also contain third-party software, scripts, diagnostic tools, and malware operating under a compromised account. Any process that knows the pipe name and has sufficient access rights can attempt to connect. Windows does not inherently know which executable the developer intended to use the pipe. For that reason, a named pipe should be treated as an exposed local interface. Before processing a request, the application must determine who connected, what that identity is allowed to do, and whether the supplied data is safe. Identity, Access Control, and Privilege Boundaries The risk is greatest when a privileged Windows service communicates with a less privileged desktop application. A service running as LocalSystem may be able to modify protected files and registry keys, launch processes, change system configuration, access other users’ data, or communicate with kernel drivers. When these operations are exposed through a named pipe, the pipe becomes an API to privileged functionality. A successful connection proves only that the client was allowed to open the pipe. It does not prove that: the client is the expected application; the connected user is authorized; the requested operation is permitted; the supplied command is safe. Pipe permissions should therefore be defined explicitly and restricted to the smallest appropriate set of identities. Broad permissions for Everyone, Authenticated Users, or all interactive users may allow unrelated processes to reach the pipe. Authentication and authorization must also remain separate. A user may be allowed to query service status but not stop the service, change protected settings, launch processes, or access arbitrary files. Sensitive commands should be authorized individually. Impersonation can help by performing operations under the client’s security context, but it must be handled carefully. The server should verify that impersonation succeeded, limit the work performed while impersonating, and always restore its original identity. Fight Back Against AI-Powered Cyberattacks See how excessive permissions can turn AI tools into a serious security risk. Learn how a practical Zero Trust strategy can help contain AI-enabled threats before they spread. Read the blog Untrusted Servers, Commands, and Data The client must verify the server just as the server verifies the client. A predictable pipe name is only an identifier. It is not a secret and does not prove which process created the pipe. An attacker may create a pipe using the expected name before the legitimate server starts, causing the client to connect to an attacker-controlled process. The first-pipe-instance option can help detect that the name has already been claimed, but it does not replace proper access controls or server identity verification. Messages received through the pipe must also be treated as untrusted input. Even an authenticated client may send: malformed or oversized payloads; invalid file or registry paths; unsupported command combinations; corrupted serialized objects; values designed to trigger error conditions. A privileged service that converts such input directly into file, registry, process, or command-line operations may become a confused deputy: the attacker supplies the instruction, while the service supplies the privileges. Requests should use strict message framing, bounded sizes, command allowlists, schema validation, path normalization, operation-specific authorization, and safe error handling. Availability and Remote Exposure Named-pipe security is not limited to privilege escalation and unauthorized commands. A malicious or malfunctioning process may repeatedly connect, hold connections open, send incomplete messages, or submit requests that consume excessive CPU, memory, or kernel resources. The server should use connection limits, timeouts, cancellation, bounded message sizes, controlled concurrency, and rate limiting where appropriate. It is also unsafe to assume that every named pipe is reachable only from the local computer. Windows named pipes can support remote access in some configurations. Pipes intended exclusively for local IPC should explicitly block network identities such as NT AUTHORITY\\NETWORK, or use a mechanism that guarantees local-only communication. The correct threat model is simple: every named-pipe connection should be considered potentially hostile until the client or server identity, permissions, requested operation, and message contents have all been verified. When a Named Pipe Becomes a Security Boundary A named pipe becomes a security boundary when the processes on its two ends run with different privileges or operate under different trust levels. A common example is a Windows service running as LocalSystem and a desktop application running under a standard user account. The service may be able to modify protected files and registry keys, start processes, change system-wide configuration, access data belonging to other users, or communicate with a kernel driver. The desktop application normally cannot perform those operations directly. When the service accepts commands through a named pipe, the pipe becomes an interface to those privileged capabilities. Any weakness in the pipe’s permissions, identity checks, command validation, or authorization logic can allow an untrusted local process to misuse the service’s privileges. A successful connection does not prove that the client is the expected application. It proves only that the connecting process had sufficient permission to open the pipe. Another process running under the same user account may have exactly the same access. The server must therefore validate the security identity behind the connection rather than relying on the process name, executable path, or secrecy of the pipe name. The server must also authorize each operation separately. A client that is allowed to request service status should not automatically be allowed to stop the service, modify protected configuration, launch a process, or request access to an arbitrary file. Authentication determines who connected; authorization determines what that identity may do. This distinction is especially important when the server processes client-controlled paths, command-line arguments, registry locations, executable names, or serialized commands. Without strict validation, the service can become a confused deputy: the client chooses the action, but the privileged service performs it. For example, a seemingly harmless request such as: Read file: C:\\ProgramData\\Product\\status.json may become dangerous if the client can replace the path with: Read file: C:\\Windows\\System32\\config\\SAM The same problem applies to requests that start processe","https:\u002F\u002Fwww.bleepingcomputer.com\u002Fnews\u002Fsecurity\u002Fnamed-pipes-under-attack-securing-windows-interprocess-communication\u002F","https:\u002F\u002Fwww.bleepstatic.com\u002Fcontent\u002Fposts\u002F2026\u002F08\u002F18\u002F0_named-pipe-header-image.jpg","2026-08-22T13:00:09+00:00","2026-08-22T14:00:28.151192+00:00",7,[18],{"name":19,"type":20},"ThreatLocker","vendor","80544778-fabb-4dcd-aa35-17492e5dcf4f",{"id":21,"icon":23,"name":24,"slug":25},null,"Vulnerabilities","vulnerabilities",[27,32,37,39],{"category":28},{"id":29,"icon":23,"name":30,"slug":31},"02371804-cf6d-4449-98de-f1a2d4d9b266","Tools","tools",{"category":33},{"id":34,"icon":23,"name":35,"slug":36},"2c8f44d4-b56e-47cf-9677-04f22c9ee78d","Identity & Access","identity-access",{"category":38},{"id":21,"icon":23,"name":24,"slug":25},{"category":40},{"id":41,"icon":23,"name":42,"slug":43},"e7b231c8-5f79-4465-8d38-1ef13aea5a14","Threat Intelligence","threat-intelligence",[]]