add file write model for express-fileupload mv

Author: esbena

javascript/ql/lib/semmle/javascript/frameworks/ExpressModules.qll

@@ -226,3 +226,30 @@ module ExpressLibraries {
     predicate producesUserControlledObjects() { isJson() or isExtendedUrlEncoded() }
   }
 }
+
+/**
+ * Provides classes for working with the `express-fileupload` package (https://github.com/richardgirges/express-fileupload);
+ */
+module FileUpload {
+  /** Gets a data flow node referring to `req.files`. */
+  private DataFlow::SourceNode filesRef(Express::RequestSource req, DataFlow::TypeTracker t) {
+    t.start() and
+    result = req.ref().getAPropertyRead("files")
+    or
+    exists(DataFlow::TypeTracker t2 | result = filesRef(req, t2).track(t2, t))
+  }
+
+  /**
+   * A call to `req.files.<name>.mv`
+   */
+  class Move extends FileSystemWriteAccess, DataFlow::MethodCallNode {
+    Move() {
+      exists(DataFlow::moduleImport("express-fileupload")) and
+      this = filesRef(_, DataFlow::TypeTracker::end()).getAPropertyRead().getAMethodCall("mv")
+    }
+
+    override DataFlow::Node getAPathArgument() { result = getArgument(0) }
+
+    override DataFlow::Node getADataNode() { none() }
+  }
+}

javascript/ql/test/query-tests/Security/CWE-022/TaintedPath/TaintedPath.expected

@@ -1535,6 +1535,12 @@ nodes
 | TaintedPath.js:214:35:214:38 | path |
 | TaintedPath.js:214:35:214:38 | path |
 | TaintedPath.js:214:35:214:38 | path |
+| express.js:8:20:8:32 | req.query.bar |
+| express.js:8:20:8:32 | req.query.bar |
+| express.js:8:20:8:32 | req.query.bar |
+| express.js:8:20:8:32 | req.query.bar |
+| express.js:8:20:8:32 | req.query.bar |
+| express.js:8:20:8:32 | req.query.bar |
 | normalizedPaths.js:11:7:11:27 | path |
 | normalizedPaths.js:11:7:11:27 | path |
 | normalizedPaths.js:11:7:11:27 | path |
@@ -6321,6 +6327,7 @@ edges
 | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:211:14:211:37 | url.par ... , true) |
 | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:211:14:211:37 | url.par ... , true) |
 | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:211:14:211:37 | url.par ... , true) |
+| express.js:8:20:8:32 | req.query.bar | express.js:8:20:8:32 | req.query.bar |
 | normalizedPaths.js:11:7:11:27 | path | normalizedPaths.js:13:19:13:22 | path |
 | normalizedPaths.js:11:7:11:27 | path | normalizedPaths.js:13:19:13:22 | path |
 | normalizedPaths.js:11:7:11:27 | path | normalizedPaths.js:13:19:13:22 | path |
@@ -9638,6 +9645,7 @@ edges
 | TaintedPath.js:212:31:212:34 | path | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:212:31:212:34 | path | This path depends on $@. | TaintedPath.js:211:24:211:30 | req.url | a user-provided value |
 | TaintedPath.js:213:45:213:48 | path | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:213:45:213:48 | path | This path depends on $@. | TaintedPath.js:211:24:211:30 | req.url | a user-provided value |
 | TaintedPath.js:214:35:214:38 | path | TaintedPath.js:211:24:211:30 | req.url | TaintedPath.js:214:35:214:38 | path | This path depends on $@. | TaintedPath.js:211:24:211:30 | req.url | a user-provided value |
+| express.js:8:20:8:32 | req.query.bar | express.js:8:20:8:32 | req.query.bar | express.js:8:20:8:32 | req.query.bar | This path depends on $@. | express.js:8:20:8:32 | req.query.bar | a user-provided value |
 | normalizedPaths.js:13:19:13:22 | path | normalizedPaths.js:11:14:11:27 | req.query.path | normalizedPaths.js:13:19:13:22 | path | This path depends on $@. | normalizedPaths.js:11:14:11:27 | req.query.path | a user-provided value |
 | normalizedPaths.js:14:19:14:29 | './' + path | normalizedPaths.js:11:14:11:27 | req.query.path | normalizedPaths.js:14:19:14:29 | './' + path | This path depends on $@. | normalizedPaths.js:11:14:11:27 | req.query.path | a user-provided value |
 | normalizedPaths.js:15:19:15:38 | path + '/index.html' | normalizedPaths.js:11:14:11:27 | req.query.path | normalizedPaths.js:15:19:15:38 | path + '/index.html' | This path depends on $@. | normalizedPaths.js:11:14:11:27 | req.query.path | a user-provided value |

javascript/ql/test/query-tests/Security/CWE-022/TaintedPath/express.js

@@ -0,0 +1,9 @@
+var express = require("express"),
+  fileUpload = require("express-fileupload");
+
+let app = express();
+app.use(fileUpload());
+
+app.get("/some/path", function (req, res) {
+  req.files.foo.mv(req.query.bar);
+});