# CVE-2026-77630: pupnp: Denial of service via blocking DNS resolution in parse_uri()/GENA callback parsing

> Remote attackers can cause denial of service in pupnp by supplying slow hostnames that block worker threads during DNS resolution.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Oct 2026
- **Updated:** 16 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-77630, GHSA-46ph-jff5-5h77, UBUNTU-CVE-2026-77630

## What is CVE-2026-77630?

CVE-2026-77630 is a high-severity denial of service vulnerability in pupnp, published on 16 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-77630?

It affects 1 product.


Products: Pupnp Project Pupnp.

## How do I fix CVE-2026-77630?

Upgrade to a fixed version.

## Is CVE-2026-77630 being exploited?

There is no known exploitation of CVE-2026-77630 in the wild and no public exploit code.

## Other vulnerabilities in pupnp

- [CVE-2021-29462](https://insights.sbomify.com/CVE-2021-29462/): DNS rebinding in pupnp (high 7.6)
- [CVE-2026-57486](https://insights.sbomify.com/CVE-2026-57486/): pupnp: NULL pointer dereference in ixmlNode_compare crashes on non-namespaced attributes (high 7.5)
- [CVE-2026-57487](https://insights.sbomify.com/CVE-2026-57487/): libupnp chunked HTTP bodies can bypass g_maxContentLength and be fully buffered (high 7.5)
- [CVE-2021-28302](https://insights.sbomify.com/CVE-2021-28302/): Denial of service in n/a (high 7.5)
- [CVE-2026-57488](https://insights.sbomify.com/CVE-2026-57488/): pupnp: Integer truncation in HTTP Content-Length parsing enables request smuggling (high 7.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-77630 and fix it if it is affected.

What it is: CVE-2026-77630 is a high-severity denial of service vulnerability in pupnp, published on 16 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-77630 in the wild and no public exploit code.

Affected product: pupnp. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-77630/ (Markdown: https://insights.sbomify.com/CVE-2026-77630/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-77630
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-77630
- OSV: https://osv.dev/vulnerability/CVE-2026-77630

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-77630/
Summaries are generated and may contain mistakes; the official description above is the record.