---
id: "CVE-2026-77630"
kind: "vulnerability"
aliases: ["CVE-2026-77630"]
title: "pupnp: hostname resolution in UPnP parser lets remote peers stall server threads"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "pupnp project pupnp", "fixed": ["22.0.4"], "affected": "< 22.0.4", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["c", "embedded", "package", "self-hosted", "upnp"]
not_affected_if: ["miniserver-not-exposed", "pupnp-not-linked"]
published_at: "2026-10-16T16:21:03+00:00"
first_seen_at: "2026-10-23T21:57:13+00:00"
updated_at: "2026-10-25T03:24:58+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77630", "first_seen_at": "2026-10-23T21:57:13+00:00"}]
---

# pupnp: hostname resolution in UPnP parser lets remote peers stall server threads

pupnp is a C SDK for UPnP devices and control points. Before 22.0.4, attacker-supplied hostnames in inbound HTTP request targets and GENA SUBSCRIBE CALLBACK headers are resolved synchronously, so a slow hostname blocks a miniserver worker.

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

## Affected

- vendor:pupnp project pupnp affected < 22.0.4 fixed 22.0.4

## How to check

- Find the pupnp version in your build, for example with `pkg-config --modversion libupnp` or by checking the vendored copy's version header.
- Confirm the library is built from source or linked into your application, and that it runs a UPnP device or control point miniserver.

## Fix

- Upgrade pupnp to `22.0.4` or later.
- Rebuild and redeploy applications that statically link or vendor pupnp.

## Timeline

- 2026-10-23T21:57:13+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-77630

## From the sources

pupnp is an SDK for development of UPnP device and control point applications. Prior to 22.0.4, parse_hostport in upnp/src/genlib/net/uri/uri.c synchronously calls getaddrinfo while parse_uri is processing attacker-supplied hostnames from inbound HTTP request targets in upnp/src/genlib/net/http/httpparser.c and GENA SUBSCRIBE CALLBACK headers handled by create_url_list in upnp/src/gena/gena_device.c. A remote unauthenticated peer can choose a slow or nonresponsive hostname and block a bounded miniserver worker for the resolver timeout, allowing a small number of requests to exhaust the thread pool and deny UPnP service. This issue is fixed in 22.0.4.

---

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