diff --git a/src/controllers/uploads.js b/src/controllers/uploads.js
index e539c79bc6..0a91cd5dcc 100644
--- a/src/controllers/uploads.js
+++ b/src/controllers/uploads.js
@@ -37,6 +37,9 @@ uploadsController.upload = function (req, res, filesIterator) {
 
 uploadsController.uploadPost = function (req, res, next) {
 	uploadsController.upload(req, res, function (uploadedFile, next) {
+		if (!parseInt(req.body.cid, 10)) {
+			return next(new Error('[[error:category-not-selected]]'));
+		}
 		var isImage = uploadedFile.type.match(/image./);
 		if (isImage) {
 			uploadAsImage(req, uploadedFile, next);
diff --git a/test/uploads.js b/test/uploads.js
index 318428c298..4133fdf9ab 100644
--- a/test/uploads.js
+++ b/test/uploads.js
@@ -77,6 +77,14 @@ describe('Upload Controllers', function () {
 			});
 		});
 
+		it('should fail to upload an image to a post with invalid cid', function (done) {
+			helpers.uploadFile(nconf.get('url') + '/api/post/upload', path.join(__dirname, '../test/files/test.png'), { cid: '0' }, jar, csrf_token, function (err, res, body) {
+				assert.equal(res.statusCode, 500);
+				assert.equal(body.error, '[[error:category-not-selected]]')
+				done();
+			});
+		});
+
 		it('should upload an image to a post', function (done) {
 			helpers.uploadFile(nconf.get('url') + '/api/post/upload', path.join(__dirname, '../test/files/test.png'), { cid: cid }, jar, csrf_token, function (err, res, body) {
 				assert.ifError(err);