GHSA-r557-wffq-wvrc @astrojs/node: Backslash-prefixed paths not recognized as internal by trailing-slash redirect

• npm @astrojs/node: >= 8.1.0, < 11.0.2 → fixed in 11.0.2

Impact With `trailingSlash: 'always'` configured, the `@astrojs/node` standalone server's static file handler appends a trailing slash to request paths and issues a `301` redirect. Paths beginning with `/\` (slash-backslash) were not recognized as internal paths, so the handler would echo the raw path back in the `Location` header. Because browsers treat `\` as `/` per the WHATWG URL specification, the resulting redirect could resolve to an external host. Preconditions: • `trailingSlash: 'always'` must be set (non-default; the default is `'ignore'`) • The request path must not have a file extension in its final segment • An attacker must deliver the crafted link to a user Patches Fixed by treating backslash-prefixed paths the same as `//`-prefixed paths in `isInternalPath()`, so they are no longer rewritten with a trailing slash. Workarounds Use the default `trailingSlash: 'ignore'` setting, which does not issue trailing-slash redirects in the static file handler. References • WHATWG URL spec: backslash normalization