# CVE-2026-102984: Astro: Malformed port in the Host header can crash the Node adapter

> A malformed Host header can crash the Astro Node adapter process when staticHeaders is enabled, causing a denial of service.

- **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-qh8j-hqjv-7m4x

## What is CVE-2026-102984?

CVE-2026-102984 is a high-severity denial of service vulnerability in withastro astro, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Astro is a web framework for content-driven websites. Prior to 11.1.3, the @astrojs/node adapter builds a request URL from the Host header, and a malformed port can make that URL invalid. The recovery path reuses the same malformed host and throws an uncaught TypeError: Invalid URL before routing begins. In the default standalone configuration, the request returns an HTTP 500 response and the server continues running, but when staticHeaders is enabled the synchronous handler does not catch the exception and the Node process terminates. Proxies and CDNs that reject malformed Host headers prevent this path from reaching the origin. The issue affects availability only and does not expose data or permit code execution. This issue is fixed in version 11.1.3.

Weakness: CWE-248 (Uncaught Exception)

## Which versions are affected by CVE-2026-102984?

2 open source packages ship an affected version, including @astrojs/node.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@astrojs/node` | npm | All versions | 11.1.3 |
| `@astrojs/node` | npm | All versions | 11.1.3 |

## How do I fix CVE-2026-102984?

Upgrade @astrojs/node to 11.1.3 or later.

## Is CVE-2026-102984 being exploited?

There is no known exploitation of CVE-2026-102984 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-102984 and fix it if it is affected.

What it is: CVE-2026-102984 is a high-severity denial of service vulnerability in withastro astro, published on 30 Sep 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-2026-102984 in the wild and no public exploit code.

Affected packages and fixed versions:
- @astrojs/node (npm): affected all versions; fixed in 11.1.3
- @astrojs/node (npm): affected all versions; fixed in 11.1.3

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-2026-102984/ (Markdown: https://insights.sbomify.com/CVE-2026-102984/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-102984
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-102984
- OSV: https://osv.dev/vulnerability/CVE-2026-102984

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-102984/
Summaries are generated and may contain mistakes; the official description above is the record.