@astrojs/node allows Astro to deploy your SSR site to Node targets. Prior to 10.0.5, requesting a static js/css resources from _astro path with an incorrect/malformed if-match header returns a 500 error with a one year cache lifetime instead of 412 in some cases. This has the effect that all subsequent requests to that file, regardless of if-match header will be served a 5xx error instead of the file until the cache expires. This vulnerability is fixed in 10.0.5.

Affected: npm: @astrojs/node

### Summary Requesting a static JS/CSS resource from the `_astro` path with an incorrect or malformed `if-match` header returns a `500` error with a one-year cache lifetime instead of `412` in some cases. As a result, all subsequent requests to that file — regardless of the `if-match` header — will be served a 5xx error instead of the file until the cache expires.

Sending an incorrect or malformed `if-match` header should always return a `412` error without any cache headers, which is not the current behavior.

### Affected Versions - `astro@5.14.1` - `@astrojs/node@9.4.4`

### Proof of Concept

Run the following command:

``` curl -s -o /dev/null -D - <host location>/_astro/_slug_.UTbyeVfw.css -H "if-match: xxx" ```

If a 5xx error is not returned, inspect the resources via the browser's web inspector and select another CSS/JS file to request until a 5xx error is returned. The behavior generally defaults to a 5xx response. Note that all static files are immutable, so the cache must be purged or disabled to reproduce reliably.

A response similar to the following is expected from CloudFront:

``` HTTP/2 500 content-type: text/html content-length: 166541 date: Thu, 09 Apr 2026 12:53:08 GMT last-modified: Wed, 21 Jan 2026 13:40:08 GMT etag: "a68349e96c2faf8861c330aeb548441a" x-amz-server-side-encryption: AES256 accept-ranges: bytes server: AmazonS3 x-cache: Error from cloudfront via: 1.1 3591be88662e5675a9dc1cc4e0a9c392.cloudfront.net (CloudFront) x-amz-cf-pop: ZRH55-P2 x-am…