diff --git a/lib/sanitize-string.js b/lib/sanitize-string.js
new file mode 100644
index 0000000..5cb8b9f
--- /dev/null
+++ b/lib/sanitize-string.js
@@ -0,0 +1,4 @@
+var NOT_SAFE_IN_XML_1_0 = /[^\x09\x0A\x0D\x20-\xFF\x85\xA0-\uD7FF\uE000-\uFDCF\uFDE0-\uFFFD]/gm;
+module.exports = function sanitizeString(str) {
+    return str.replace(NOT_SAFE_IN_XML_1_0, '');
+}
diff --git a/lib/serialize.js b/lib/serialize.js
index 2a4f667..c41aa00 100644
--- a/lib/serialize.js
+++ b/lib/serialize.js
@@ -1,4 +1,5 @@
 var xmlbuilder = require('xmlbuilder');
+var sanitizeString = require('./sanitize-string');
 
 module.exports = function serialize (testCases) {
   var rootXml = xmlbuilder.create('testsuites');
@@ -33,8 +34,8 @@ module.exports = function serialize (testCases) {
           }
       }
       if(i === suite.asserts.length -1) {
-        suite.extra.forEach(function (e) {
-          testCaseElement.ele('system-out', e);
+        suite.extra.forEach(function (extraContent) {
+          testCaseElement.ele('system-out', sanitizeString(extraContent));
         });
       }
     });
diff --git a/test.txt b/test.txt
new file mode 100644
index 0000000..22eb60a
Binary files /dev/null and b/test.txt differ
diff --git a/unit-tests/serialization-tests.js b/unit-tests/serialization-tests.js
index 674c447..02232a7 100644
--- a/unit-tests/serialization-tests.js
+++ b/unit-tests/serialization-tests.js
@@ -112,6 +112,30 @@ var serialize = require('../lib/serialize');
                 }]
             }
         }
+    },
+    {
+        name: 'removes null characters from log',
+        input: [{
+          extra: [ '\u0000' ],
+          asserts: [
+              { ok: true, id: 1, name: 'should be equal' },
+              { ok: true, id: 2, name: 'should be equal' }
+          ]
+        }],
+        expected: {
+            testsuites: {
+                testsuite: [{
+                    '$': { tests: '2', failures: '0', name: '', errors: '0' },
+                    testcase: [
+                        { '$': { name: '#1 should be equal' } },
+                        {
+                            '$': { name: '#2 should be equal' },
+                            'system-out': [ '' ]
+                        },
+                    ],
+                }]
+            }
+        }
     }
 ].forEach(function(testCase) {
     test('serializes: ' + testCase.name, function (assert) {
diff --git a/unit-tests/xml-sanitization-tests.js b/unit-tests/xml-sanitization-tests.js
new file mode 100644
index 0000000..641f1ba
--- /dev/null
+++ b/unit-tests/xml-sanitization-tests.js
@@ -0,0 +1,27 @@
+var test = require('tape');
+var sanitizeString = require('../lib/sanitize-string');
+
+[
+    '\u0000',
+    '\u0001'
+].forEach(function(invalidCharacter){
+    test(
+        'it strips the invalid character:' + invalidCharacter.charCodeAt(0),
+        function(assert){
+            assert.equal(sanitizeString(invalidCharacter), '');
+            assert.end();
+        }
+    );
+});
+
+[
+    '\u000A',
+].forEach(function(validCharacter){
+    test(
+        'it doesn\'t strip the valid character:' + validCharacter.charCodeAt(0),
+        function(assert){
+            assert.equal(sanitizeString(validCharacter), validCharacter);
+            assert.end();
+        }
+    );
+});