GHSA-P36Q-Q72M-GCHR
Vulnerability from github – Published: 2026-03-26 16:52 – Updated: 2026-03-27 21:11Summary
A pathname parsing discrepancy in srvx's FastURL allows middleware bypass on the Node.js adapter when a raw HTTP request uses an absolute URI with a non-standard scheme (e.g. file://).
Details
When Node.js receives an absolute URI in the request line (e.g. GET file://hehe?/internal/run HTTP/1.1), req.url is set verbatim to file://hehe?/internal/run. Since this doesn't start with /, NodeRequestURL passes it directly to FastURL as a string, which stores it in #href for lazy manual parsing.
FastURL#getPos() locates the pathname by finding :// then scanning for the next / — but this fails for URLs like file://hehe?/internal/run where a ? appears before the first / after the authority. The manual parser extracts pathname as /internal/run, while native URL correctly parses it as pathname / with search ?/internal/run.
This discrepancy means the router (using the fast-path) matches /internal/run, but if any middleware triggers a deopt to native URL (e.g. by accessing hostname), subsequent middleware sees a different pathname — bypassing route-based middleware guards.
This is a bypass of CVE-2026-33131.
Impact
Route-based middleware (auth guards, rate limiters, etc.) can be bypassed on the Node.js adapter when a prior middleware triggers FastURL deopt. Requires sending a raw HTTP request (not possible from browsers).
Fix
srvx FastURL constructor now deopts to native URL for any string not starting with /, ensuring consistent pathname resolution.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "srvx"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.11.13"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-33732"
],
"database_specific": {
"cwe_ids": [
"CWE-706"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-26T16:52:08Z",
"nvd_published_at": "2026-03-26T18:16:31Z",
"severity": "MODERATE"
},
"details": "## Summary\n\nA pathname parsing discrepancy in srvx\u0027s `FastURL` allows middleware bypass on the Node.js adapter when a raw HTTP request uses an absolute URI with a non-standard scheme (e.g. `file://`).\n\n## Details\n\nWhen Node.js receives an absolute URI in the request line (e.g. `GET file://hehe?/internal/run HTTP/1.1`), `req.url` is set verbatim to `file://hehe?/internal/run`. Since this doesn\u0027t start with `/`, `NodeRequestURL` passes it directly to `FastURL` as a string, which stores it in `#href` for lazy manual parsing.\n\n`FastURL#getPos()` locates the pathname by finding `://` then scanning for the next `/` \u2014 but this fails for URLs like `file://hehe?/internal/run` where a `?` appears before the first `/` after the authority. The manual parser extracts pathname as `/internal/run`, while native `URL` correctly parses it as pathname `/` with search `?/internal/run`.\n\nThis discrepancy means the router (using the fast-path) matches `/internal/run`, but if any middleware triggers a deopt to native `URL` (e.g. by accessing `hostname`), subsequent middleware sees a different pathname \u2014 bypassing route-based middleware guards.\n\nThis is a bypass of [CVE-2026-33131](https://github.com/h3js/h3/security/advisories/GHSA-3vj8-jmxq-cgj5).\n\n## Impact\n\nRoute-based middleware (auth guards, rate limiters, etc.) can be bypassed on the Node.js adapter when a prior middleware triggers `FastURL` deopt. Requires sending a raw HTTP request (not possible from browsers).\n\n## Fix\n\nsrvx `FastURL` constructor now deopts to native `URL` for any string not starting with `/`, ensuring consistent pathname resolution.",
"id": "GHSA-p36q-q72m-gchr",
"modified": "2026-03-27T21:11:10Z",
"published": "2026-03-26T16:52:08Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/h3js/h3/security/advisories/GHSA-p36q-q72m-gchr"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33732"
},
{
"type": "WEB",
"url": "https://github.com/h3js/srvx/commit/de0d69901c357f36a39b7e13eebef6c930652baa"
},
{
"type": "PACKAGE",
"url": "https://github.com/h3js/srvx"
},
{
"type": "WEB",
"url": "https://github.com/h3js/srvx/releases/tag/v0.11.13"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "srvx is vulnerable to middleware bypass via absolute URI in request line "
}
Sightings
| Author | Source | Type | Date | Other |
|---|
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