Prototype · Preview: every server in the official registry, synced every 30 minutes. Reviews and accounts come in a later step.
PopNx MCPMCP servers for people who use AI · explained in plain words

valvur

by MaverickHQversion 1.6.1i★ –iRuns on your computer
Registry nameio.github.MaverickHQ/valvur

Install

Overview

Description from the maker (original English)

Offline security scanning for AI-generated code: seven open-source scanners in one MCP server.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs on your computer
  • Transport: stdio
  • Category: Cybersecurity

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on your computer with your user’s permissions (files, network, apps).
  • The registry lists no key to fill in.

You need

  • PyPIPython’s uv installed (for the uvx command)

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "valvur": {
      "command": "uvx",
      "args": [
        "valvur",
        "mcp"
      ]
    }
  }
}

Run this in your terminal

claude mcp add valvur -- uvx valvur mcp

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "valvur": {
      "command": "uvx",
      "args": [
        "valvur",
        "mcp"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "valvur": {
      "type": "stdio",
      "command": "uvx",
      "args": [
        "valvur",
        "mcp"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified with the GitHub account MaverickHQ, which owns the repo

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • – Not applicable

    Endpoint responds

    This one runs on your computer; there is no internet endpoint

  • – Not applicable

    Sign-in with OAuth

    Runs on your computer and uses local settings instead

  • … Not checked yet

    No hidden instructions in tool descriptions

    Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Cybersecurityi

  • More stars than 0% of the other 996 servers in this category
  • Published to the registry more recently than 84% of the other 996 servers in this category
  • Basic checks equal to or better than 100% of the other 996 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is valvur safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.6.1) reached the registry 7 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Python (uv) on your computer.

What can I use instead?

In the same category: Action1 MCP by usefulapi, QNSQY, EchelonGraph CVE & Exposure

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Read endpoints, missing updates, CVE vulnerabilities, installed software and reports in Action1.

Runs in the cloudUpdated today
Install

QNSQY

by quantumsequrity

Linux only, local: post-quantum CBOM scan, encrypt to public keys, verify. Takes no secrets

Runs on your computerUpdated today
Install

CVE, KEV, EPSS, SBOM and advisory lookups; per-CVE exposure from Shodan data (© Shodan). Keyless.

Computer or cloudUpdated today
Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

Offline security scanning for AI-generated code.

Seven open-source scanners and AI-specific checks, in one command and one ranked report.

Scorecard's Code-Review, Branch-Protection and Contributors checks need a second maintainer; valvur has one (MAINTAINERS.md).

Status: `1.6.1`, the version this tree declares; the PyPI badge above shows what pip install valvur serves, and the CHANGELOG what each version changed.

In Claude Code: /plugin marketplace add MaverickHQ/valvur, then /plugin install valvur@valvur, and ask it to scan the project.

From a terminal, with Docker or Podman running: uvx valvur scan.

Why valvur

  • Seven scanners, one report. Gitleaks, Trivy, OSV-Scanner, Opengrep, Checkov, zizmor and Syft, pinned, installed and run for you in one container, beside valvur's own checks for AI-written code. A vulnerability two of them report is one finding, not two, and everything is ranked together.
  • Nothing leaves your machine, provably. No account, no API key, no telemetry. The Scanners run in one container with no network interface, and your source is copied in, never mounted. Every fetch of public data is recorded in run.json, beside what left the machine: nothing. One command checks it.
  • Built for how AI-generated code breaks. Models invent package names that attackers then register; agent instruction files carry injected directives and hidden Unicode; agent settings leak tokens. valvur checks for each, offline, beside the classic secrets, vulnerable dependencies and misconfigurations.
  • Ten findings that matter, not four hundred. Findings are ranked by whether attackers are exploiting them, from CISA KEV and FIRST EPSS rather than CVSS alone, grouped by rule and directory, with development-only dependencies demoted.
  • You stay in charge. valvur proposes fixes and never applies them. An agent told to reach zero findings can delete code or write suppressions instead, and *the finding disappeared* is not *the vulnerability is fixed*.

What it finds

areawhat valvur reportsfound by
Hallucinated packagesdependencies that do not exist, or sit one edit from a popular name, checked offline against every name on PyPI, npm, RubyGems, Packagist and crates.iovalvur's dependency-reality Check
Malicious packagesdependencies published as malicious, from OpenSSF's malicious-packagesOSV-Scanner, and the same Check
Agent configurationinjected directives, hidden Unicode, unpinned MCP servers, blanket approval, hooks that run a command, settings that would leakvalvur's ai-artifact Check
Vulnerable dependenciesknown CVEs from lockfiles, ranked by exploitation, with the direct package to bumpTrivy, OSV-Scanner
Secretscredentials in the files and in git historyGitleaks
Codeinjection, path traversal, SSRF, open redirects, XXE and insecure cookies, and model output reaching eval, a shell, a query or the DOMOpengrep, with valvur's rules
InfrastructureTerraform, CloudFormation, Kubernetes and Dockerfile misconfigurationCheckov
CI workflowsunpinned actions, write permissions, template injectionzizmor
Licences and SBOMa missing or contradictory project licence; a CycloneDX SBOM when asked forvalvur's licence-file Check, Syft

What it checks, rule by rule, and what it cannot see: how valvur works.

How it works

  1. A small host shim decides what a scan reads (the files git would publish, plus .env* files and agent configuration), fetches the public data it needs, and records each fetch.
  2. One Scan Container, with no network interface, runs every Scanner over a copy of those files fed on stdin. Nothing in it can change your source.
  3. One findings model normalises and ranks what they report, and the shim writes the Results Folder into your project:
.security-scan/          ← ignores itself in git, so it is never committed

├── SUMMARY.md ← start here: the verdict, anything that failed, the top groups ├── REMEDIATION.md ← a ranked proposal: you choose what to apply ├── findings.json ← every finding, normalised, secrets redacted ├── results.sarif ← SARIF 2.1.0, for code scanning and IDEs └── run.json ← what ran, what was fetched, and what left the machine: nothing

A scan ends findings, clean or inconclusive. It never says clean when stale data, an uninspected ecosystem or a Scanner that did not finish cannot support it, and it says why.

Measured, not claimed

How much of what valvur claims it finds is measured as the Score: nine tracks scored by the OWASP Benchmark's formula, with a ratchet that no change may fall more than two points under. It is 74.1 out of 100, the same on Linux and on macOS.

trackwhat it holdsscore
sast-pythonthe OWASP Benchmark for Python40.9
sast-jsvalvur's JavaScript twins: ten weaknesses, vulnerable and fixed55.0
secretsten formats, in files and in history100.0
dependencieslockfiles pinned to vulnerable versions; known-malicious packages100.0
package-realitynonexistent, near-miss and malicious names100.0
agent-configurationplanted directives and hidden Unicode, against real files94.3
infrastructureTerraform, Kubernetes, Dockerfile and Actions faults95.0
real-code-precision48 maintained projects, every finding labelled by hand2.3
llm-outputmodel output reaching code, a shell, a query or the DOM: generated twins and five published advisories79.0

Track 8 is precision on maintained code, where almost nothing is a vulnerability: 3 of its 171 findings are real. Track 9 measures the rules for model output reaching a sink: they catch 30 of 34 generated flows with no false alarm, and none of five published advisories in LangChain, LlamaIndex and Vanna, whose flows each cross a function. Each rule's precision is in docs/RULES.md, and the method, the gates and what valvur does not claim are in docs/EVALUATING.md. Read that one sceptically.

Use it

In an AI coding agent

The Claude Code plugin brings the MCP server, a skill that runs the workflow, and a hook that asks you before the agent installs a package valvur flags. Kiro takes it as a power. Any MCP client runs the server with uvx --from valvur valvur-mcp. The agents' guide has the configuration for eleven clients, the seven tools, and the permissions a *don't ask* mode needs.

From the command line

The Scanners run in a container, so the machine needs Docker or Podman; valvur doctor says what is missing.

pip install valvur          # or: uv tool install valvur

valvur scan # offline by default; --profile full adds the registries' answers valvur check npm left-pad # before an install: real, a near-miss, or malicious? valvur gate . --fail-on high --no-inconclusive

The command-line guide has every command, what a first scan fetches, the Results Folder, and the settings files.

In CI
- uses: MaverickHQ/valvur-action@16b19e275f843419887873ed536a71f872607e24 # v0.2

with: { fail-on: high, no-inconclusive: "true" }

The action scans, uploads results.sarif to code scanning and gates the job. The CI guide covers the gate, the image as a step of its own, and GitLab.

Built on open-source scanners

valvur builds no detection engine. Seven open-source Scanners do that and deserve the credit; valvur adds one File Set, one findings model, exploit-aware ranking, and three Checks of its own. All of them run in one container, fed a copy of the files. run.json records the version of each that ran, and raw/ keeps what each said.

ScannerLicenceReadsRuns
GitleaksMITSecrets in the files scanned and in git history, the newest 5,000 commits or 200 MBalways
TrivyApache-2.0Known vulnerabilities in dependencies, from lockfiles, against its database in the host cachealways
OSV-ScannerApache-2.0Lockfiles against OSV's data, which carries the known-malicious MAL- packages nothing else here reports. On offline, OSV's offline database for each ecosystem present, fetched into the host cache; on full, OSV.dev's API, which receives lockfile names and versionsalways
OpengrepLGPL-2.1Static analysis: pinning rules, a sink inventory at INFO, taint rules from a model call to a sink, and taint rules from request dataalways
CheckovApache-2.0Infrastructure misconfiguration: Terraform, CloudFormation, Kubernetes, Dockerfiles, other CI systemswhere there is infrastructure other than GitHub workflows
zizmorMITGitHub Actions workflows: unpinned actions, write permissions, template injectionwhere there are workflows
SyftApache-2.0The SBOM, and the dependency licences read from itwhen asked for: scan --sbom, or sbom = true under [scan]
CheckReads
ai-artifactAgent configuration: injected directives, hidden Unicode, unpinned MCP servers, blanket approval, hooks that run a command, and local settings that would leak
dependency-realityEvery declared dependency against the Name Index: does it exist, and on full, how old and how adopted is it. Every declared or locked one against the known-malicious list, built daily from OpenSSF's malicious-packages
licence-fileThe project's own licence: missing, or contradicting what the manifest declares

Exploit intelligence comes from CISA KEV and FIRST EPSS: public primary sources, auditable and mirrorable. No proprietary database, and nothing to lock you in.

What it does not do

  • No reachability analysis. We do not prove a vulnerable function is called.
  • No autonomous fixing. You choose the fixes.
  • No penetration testing. No DAST, no exploitation, no scanning of deployed systems.
  • No code-quality analysis. Security only.
  • We will not out-detect commercial SAST. We win on trust, breadth in one artifact, and prioritisation, not on engine depth.

Platforms

platformsupport
Linux, Docker and PodmanSupported. Every commit runs the e2e suite against Docker and Podman on amd64, and against Docker on arm64, and a scan with the published image on both; the acceptance set runs nightly on GitHub's Linux runner

| macOS, Docker Desktop or Podman | Supported, and tested by hand on

Only the beginning is shown; read the rest in the repo

Ask PopNx