const os = require('os'); const uuid = require('node-uuid'); const fs = require('fs'); const path = require('path'); (function main() { var tmpLocation = path.join( os.tmpdir ? os.tmpdir() : os.tmpDir(), // $ Source 'something', uuid.v4().slice(0, 8) ); fs.writeFileSync(tmpLocation, content); // $ Alert var tmpPath = "/tmp/something"; // $ Source fs.writeFileSync(path.join("./foo/", tmpPath), content); fs.writeFileSync(path.join(tmpPath, "./foo/"), content); // $ Alert fs.writeFileSync(path.join(tmpPath, "./foo/"), content, {mode: 0o600}); fs.writeFileSync(path.join(tmpPath, "./foo/"), content, {mode: mode}); // OK - assumed unknown mode is secure fs.writeFileSync(path.join(tmpPath, "./foo/"), content, {mode: 0o666}); // $ Alert - explicitly insecure const tmpPath2 = path.join(os.tmpdir(), `tmp_${Math.floor(Math.random() * 1000000)}.md`); // $ Source fs.writeFileSync(tmpPath2, content); // $ Alert fs.openSync(tmpPath2, 'w'); // $ Alert fs.openSync(tmpPath2, 'w', 0o600); })