diff --git a/encryption.js b/encryption.js
index 1a0df246..c403af88 100644
--- a/encryption.js
+++ b/encryption.js
@@ -1,6 +1,7 @@
 let CryptoJS = require('crypto-js');
 
 module.exports.encrypt = function(data, password) {
+  if (data.length < 10) throw new Error('data length cant be < 10');
   let ciphertext = CryptoJS.AES.encrypt(data, password);
   return ciphertext.toString();
 };
@@ -11,5 +12,11 @@ module.exports.decrypt = function(data, password) {
   try {
     str = bytes.toString(CryptoJS.enc.Utf8);
   } catch (e) {}
+
+  // for some reason, sometimes decrypt would succeed with wrong password and return random couple of characters.
+  // at least in nodejs environment. so with this little hack we are not alowing to encrypt data that is shorter than
+  // 10 characters, and thus if decrypted data is less than 10 characters we assume that decrypt actually failed.
+  if (str.length < 10) return false;
+
   return str;
 };
diff --git a/screen/selftest.js b/screen/selftest.js
index 8fcdeca5..aa34ac8e 100644
--- a/screen/selftest.js
+++ b/screen/selftest.js
@@ -202,13 +202,12 @@ export default class Selftest extends Component {
       }
 
       //
-
-      let crypted = encryption.encrypt('data', 'password');
+      const data2encrypt = 'really long data string';
+      let crypted = encryption.encrypt(data2encrypt, 'password');
       let decrypted = encryption.decrypt(crypted, 'password');
 
-      if (decrypted !== 'data' && crypted && decrypted) {
-        errorMessage += 'encryption lib is not ok; ';
-        isOk = false;
+      if (decrypted !== data2encrypt && crypted && decrypted) {
+        throw new Error('encryption lib is not ok');
       }
 
       //
diff --git a/tests/unit/encryption.js b/tests/unit/encryption.js
index 73834f89..67f4e6aa 100644
--- a/tests/unit/encryption.js
+++ b/tests/unit/encryption.js
@@ -5,19 +5,28 @@ let c = require('../../encryption')
 describe('unit - encryption', function () {
 
   it('encrypts and decrypts', function () {
-    let crypted = c.encrypt('data', 'password');
-    let decrypted = c.decrypt(crypted, 'password');
+    const data2encrypt = 'really long data string bla bla really long data string bla bla really long data string bla bla';
+    const crypted = c.encrypt(data2encrypt, 'password');
+    const decrypted = c.decrypt(crypted, 'password');
 
     assert.ok(crypted);
     assert.ok(decrypted);
-    assert.equal(decrypted, 'data');
-    assert.ok(crypted !== 'data');
+    assert.equal(decrypted, data2encrypt);
+    assert.ok(crypted !== data2encrypt);
 
     let decryptedWithBadPassword
     try {
       decryptedWithBadPassword = c.decrypt(crypted, 'passwordBad');
     } catch (e) {}
     assert.ok(!decryptedWithBadPassword)
+
+    let exceptionRaised = false;
+    try {
+      c.encrypt('yolo', 'password');
+    } catch (_) {
+      exceptionRaised = true;
+    }
+    assert.ok(exceptionRaised);
   })
 
   it('handles ok malformed data', function() {