# CVE-2026-33732: srvx is vulnerable to middleware bypass via absolute URI in request line

> Attackers can bypass middleware security checks in srvx by using absolute URIs with non-standard schemes in HTTP requests.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Mar 2026
- **Updated:** 27 Mar 2026
- **Also known as:** GHSA-p36q-q72m-gchr

## What is CVE-2026-33732?

CVE-2026-33732 is a medium-severity vulnerability in h3js srvx, published on 26 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

srvx is a universal server based on web standards. Prior to version 0.11.13, 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://`). Starting in version 0.11.13, the `FastURL` constructor now deopts to native `URL` for any string not starting with `/`, ensuring consistent pathname resolution.

Weakness: CWE-706 (Use of Incorrectly-Resolved Name or Reference)

## Which versions are affected by CVE-2026-33732?

2 open source packages ship an affected version, including srvx. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `srvx` | npm | All versions | 0.11.13 |
| `srvx` | npm | All versions | 0.11.13 |

Products: H3 Srvx.

## How do I fix CVE-2026-33732?

Upgrade srvx to 0.11.13 or later.

## Is CVE-2026-33732 being exploited?

There is no known exploitation of CVE-2026-33732 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33732 and fix it if it is affected.

What it is: CVE-2026-33732 is a medium-severity vulnerability in h3js srvx, published on 26 Mar 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-2026-33732 in the wild and no public exploit code.

Affected packages and fixed versions:
- srvx (npm): affected all versions; fixed in 0.11.13
- srvx (npm): affected all versions; fixed in 0.11.13

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-2026-33732/ (Markdown: https://insights.sbomify.com/CVE-2026-33732/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33732
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33732
- OSV: https://osv.dev/vulnerability/CVE-2026-33732

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33732/
Summaries are generated and may contain mistakes; the official description above is the record.