registry / Remote code execution / @caelo-cms/mcp-server / 0.10.55

@caelo-cms/mcp-server@0.10.55

MCP servers for Caelo CMS: `caelo_chat` (talk to Caelo's own AI) and the admin-scoped Power-MCP (the full chat-runner tool catalogue, driven by your own agent). Lets Claude Code (or any MCP-aware client) drive a Caelo install from outside the browser.

AI Security Review

scanned 3d ago · by lpm-firewall-ai

The startup handshake runs a version selected by the configured admin, which presents a conditional remote code execution risk and warrants a warning. Source inspection shows package-scoped version selection over HTTPS, not a confirmed attack or install-time execution.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

Starting either package binary when the configured admin reports a different release.

Impact

The admin response can select which release runs, so a compromised or improperly controlled admin could cause a different package release to execute.

Mechanism

The package accepts an exact semantic version from the admin over HTTPS and uses bunx to run this package at that version.

AI rationale

Evidence

dist/index.jsdist/version-handshake.jsdist/http.js

Network endpoints1

/api/mcp/version

Decision evidence

public snapshot

AI called this Suspicious at 87.0% confidence as Dangerous Capability with medium false-positive risk.

Evidence for warning

The manifest defines a build-only prepublishOnly script, with no preinstall, install, or postinstall hook.
The main binary calls the release handshake when it starts.
The handshake requests a version from the configured admin at /api/mcp/version using the configured token.
A version mismatch constructs a bunx command for this package at the admin-returned version, then launches it as a child process.
The handshake requires HTTPS except for loopback admin URLs.
The remote version must match an exact semantic version before it is used.

Evidence against

The release selection is limited to this package and comes from the configured admin; the source does not show an unrelated payload recipient or malicious action.

Behavioral surface

Source

ChildProcessEnvironmentVarsFilesystemNetwork

Supply chain

HighEntropyStringsUrlStrings

Manifest

Source & flagged code

3 flagged

dist/ingress-auth.jsView file

Lines 8-48javascript

8 * runs, so the shim has to satisfy both gates: IAP first, Caelo second

9 * (CLAUDE.md §11.B — IAP stays the first line of defense).

10 *

11 * Cloud Run native IAP uses a Google-managed OAuth client, which does not

12 * allow programmatic access with user tokens. What it does accept is a

13 * JWT signed by an allowlisted service account (Google's documented

14 * "service account JWT" path): `iss`/`sub` = the SA, `aud` = the admin

15 * origin with a path wildcard, signed via the IAM Credentials `signJwt`

16 * API. The provisioner creates that SA (`caelo-mcp@<project>`), allowlists

17 * it on IAP and lets every IAP-allowlisted operator impersonate it, so the

18 * operator's own `gcloud auth application-default login` is all the shim

19 * needs — no service-account keys on laptops (CLAUDE.md §11.C).

20 *

21 * Active only when `CAELO_IAP_SERVICE_ACCOUNT` is set (the admin's

22 * /settings/mcp page puts it into the `claude mcp add` command on IAP

23 * installs); otherwise requests go out exactly as before.

24 */

25import { GoogleAuth } from "google-auth-library";

26/** Signed JWTs live at most 1 hour; refresh a minute before expiry. */

27const TOKEN_LIFETIME_S = 3600;

28const REFRESH_MARGIN_S = 60;

29/** `https://admin.example.com/anything` → `https://admin.example.com/*` (the JWT `aud`). */

30export function iapAudience(adminUrl) {

Critical

Hardcoded Runtime Data Exfiltration

Source sends credentials or rich application records to a package-controlled external receiver enabled by default.

dist/ingress-auth.jsView on unpkg · L28

Critical

Trigger Reachable Dangerous Capability

A package entrypoint or install-time lifecycle script reaches a source file with blocking dangerous behavior.

dist/ingress-auth.jsView on unpkg · L28

31 return `${new URL(adminUrl).origin}/*`;

32}

33async function adcAccessToken() {

34 const auth = new GoogleAuth({ scopes: ["https://www.googleapis.com/auth/cloud-platform"] });

35 const token = await auth.getAccessToken();

36 if (!token)

37 throw new Error("Application Default Credentials returned no access token");

38 return token;

39}

40export function createIngressAuth(env, deps = {}) {

41 const configured = env.CAELO_IAP_SERVICE_ACCOUNT?.trim();

42 if (!configured)

43 return null;

44 const serviceAccount = configured;

45 if (!env.CAELO_ADMIN_URL)

46 throw new Error("CAELO_IAP_SERVICE_ACCOUNT is set but CAELO_ADMIN_URL is not");

47 const audience = iapAudience(env.CAELO_ADMIN_URL);

48 const getAccessToken = deps.getAccessToken ?? adcAccessToken;

dist/version-handshake.js#virtual:normalized:round1View file

•stage = ast_semantic_analysis; reason = ast_parse_error; limitedFiles = 1

High

Semantic Analysis Limited

A bounded semantic-analysis stage reached its safety limit; remaining detectors completed, but this package requires AI review.

dist/version-handshake.js#virtual:normalized:round1View on unpkg

Source & flagged code

3 flagged · loading source

dist/ingress-auth.jsView file

28const REFRESH_MARGIN_S = 60; L29: /** `https://admin.example.com/anything` → `https://admin.example.com/*` (the JWT `aud`). */ L30: export function iapAudience(adminUrl) { ... L66: headers: { authorization: `Bearer ${accessToken}`, "content-type": "application/json" }, L67: body: JSON.stringify({ L68: payload: JSON.stringify({ ... L77: if (!res.ok) { L78: const detail = await res.text().catch(() => ""); L79: throw new Error(`IAP: could not sign an access token as ${serviceAccount} (HTTP ${res.status}). ` + ... L103: let processIngress; L104: /** Ingress headers for this process, configured from `process.env` on first use. */ L105: export async function ingressHeaders() {

Critical

Hardcoded Runtime Data Exfiltration

Source sends credentials or rich application records to a package-controlled external receiver enabled by default.

dist/ingress-auth.jsView on unpkg · L28

28Trigger-reachable chain: manifest.main -> dist/index.js -> dist/admin-server.js -> dist/http.js -> dist/ingress-auth.js L28: const REFRESH_MARGIN_S = 60; L29: /** `https://admin.example.com/anything` → `https://admin.example.com/*` (the JWT `aud`). */ L30: export function iapAudience(adminUrl) { ... L66: headers: { authorization: `Bearer ${accessToken}`, "content-type": "application/json" }, L67: body: JSON.stringify({ L68: payload: JSON.stringify({ ... L77: if (!res.ok) { L78: const detail = await res.text().catch(() => ""); L79: throw new Error(`IAP: could not sign an access token as ${serviceAccount} (HTTP ${res.status}). ` + ... L103: let processIngress; L104: /** Ingress headers for this process, configured from `process.env` on first use. */ L105: export async function ingressHeaders

Findings

2 Critical1 High3 Medium6 Low

CriticalHardcoded Runtime Data Exfiltrationdist/ingress-auth.js

CriticalTrigger Reachable Dangerous Capabilitydist/ingress-auth.js

HighSemantic Analysis Limiteddist/version-handshake.js#virtual:normalized:round1

MediumNetwork

MediumEnvironment Vars

MediumStructural Risk Force Deep Review

LowNon Install Lifecycle Scripts

LowScripts Present

LowFilesystem

LowHigh Entropy Strings

LowUrl Strings

LowCopyleft License

Affected versions and remediation

This report applies to @caelo-cms/mcp-server@0.10.55.

See all versions of @caelo-cms/mcp-server for other recorded verdicts.

Review the evidence and your use of @caelo-cms/mcp-server@0.10.55 before allowing it. Restrict the permissions described in this report.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.

Evidence last updated: 2026-10-19 19:28:56.438Z (UTC).

Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.