---
id: "CVE-2026-115793"
kind: "vulnerability"
aliases: ["CVE-2026-115793"]
title: "P-Net: unknown RPC requests exhaust sessions, device stops answering until restart"
severity: "high"
cvss: 8.7
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["embedded", "industrial-control", "p-net", "package", "profinet"]
not_affected_if: ["isolated-network", "no-profinet", "patched-p-net"]
published_at: "2026-10-29T16:17:58+00:00"
first_seen_at: "2026-10-29T16:25:56+00:00"
updated_at: "2026-10-29T16:29:21+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115793", "first_seen_at": "2026-10-29T16:25:56+00:00"}]
---

# P-Net: unknown RPC requests exhaust sessions, device stops answering until restart

P-Net, a PROFINET device stack, leaves the RPC session open when a request names an unknown interface or object UUID and never times it out. Repeated requests exhaust the sessions, so the device stops answering RPC requests until it is restarted, which is a remote denial of service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check whether the device firmware or library embeds P-Net, and which version: `unknown` if the sources do not say how to read it
- Confirm whether the device is reachable from untrusted networks on the PROFINET RPC port (UDP 34964 is the usual PROFINET port, from general knowledge, not the sources)

## Fix

- P-Net: move to `1.0.3` or later

## Timeline

- 2026-10-29T16:25:56+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115793

## From the sources

P-Net before 1.0.3 does not release the RPC session allocated for an RPC request that names an unknown interface or object UUID, and does not start a timeout for it. Repeated requests with different activity UUIDs exhaust the available sessions. Once they are exhausted the device no longer answers new RPC requests, including Endpoint Mapper Lookup and Connect, until it is restarted. A remote unauthenticated attacker can use this to cause a denial of service.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_