diff --git a/requirements.txt b/requirements.txt
index 05b21086..9769ddb3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -25,6 +25,7 @@ celery==3.1.12
 redis==2.10.3
 Unidecode==0.04.16
 raven==5.1.1
+bleach==1.4
 
 # Comment it if you are using python >= 3.4
 enum34==1.0
diff --git a/taiga/mdrender/service.py b/taiga/mdrender/service.py
index baeb6c3d..f9dc0ee5 100644
--- a/taiga/mdrender/service.py
+++ b/taiga/mdrender/service.py
@@ -16,6 +16,23 @@
 
 import hashlib
 import functools
+import bleach
+
+# BEGIN PATCH
+import html5lib
+from html5lib.serializer.htmlserializer import HTMLSerializer
+
+def _serialize(domtree):
+    walker = html5lib.treewalkers.getTreeWalker('etree')
+    stream = walker(domtree)
+    serializer = HTMLSerializer(quote_attr_values=True,
+                                omit_optional_tags=False,
+                                alphabetical_attributes=True)
+
+    return serializer.render(stream)
+
+bleach._serialize = _serialize
+### END PATCH
 
 from django.core.cache import cache
 from django.utils.encoding import force_bytes
@@ -34,6 +51,15 @@ from .extensions.mentions import MentionsExtension
 from .extensions.references import TaigaReferencesExtension
 
 
+ALLOWED_TAGS = bleach.ALLOWED_TAGS + ["p", "table", "th", "tr", "td", "h1",
+               "h2", "h3", "div", "pre", "span", "hr", "dl", "dt", "dd", "sup",
+               "img", "del"]
+ALLOWED_ATTRS = bleach.ALLOWED_ATTRIBUTES
+ALLOWED_ATTRS["a"] = ["href", "title", "alt"]
+ALLOWED_ATTRS["img"] = ["alt", "src"]
+ALLOWED_ATTRS["*"] = ["class"]
+
+
 def _make_extensions_list(wikilinks_config=None, project=None):
     return [AutolinkExtension(),
             AutomailExtension(),
@@ -86,12 +112,12 @@ def _get_markdown(project):
 @cache_by_sha
 def render(project, text):
     md = _get_markdown(project)
-    return md.convert(text)
+    return bleach.clean(md.convert(text), tags=ALLOWED_TAGS)
 
 
 def render_and_extract(project, text):
     md = _get_markdown(project)
-    result = md.convert(text)
+    result = bleach.clean(md.convert(text), tags=ALLOWED_TAGS)
     return (result, md.extracted_data)
 
 
diff --git a/tests/integration/test_mdrender.py b/tests/integration/test_mdrender.py
index a905b4c5..700fb465 100644
--- a/tests/integration/test_mdrender.py
+++ b/tests/integration/test_mdrender.py
@@ -33,7 +33,7 @@ dummy_project.slug = "test"
 def test_proccessor_valid_user_mention():
     factories.UserFactory(username="user1", full_name="test name")
     result = render(dummy_project, "**@user1**")
-    expected_result = "<p><strong><a alt=\"test name\" class=\"mention\" href=\"/profile/user1\" title=\"test name\">&commat;user1</a></strong></p>"
+    expected_result = "<p><strong><a alt=\"test name\" class=\"mention\" href=\"/profile/user1\" title=\"test name\">@user1</a></strong></p>"
     assert result == expected_result
 
 
diff --git a/tests/unit/test_mdrender.py b/tests/unit/test_mdrender.py
index a3ef0c93..81679f88 100644
--- a/tests/unit/test_mdrender.py
+++ b/tests/unit/test_mdrender.py
@@ -43,7 +43,7 @@ def test_proccessor_valid_us_reference():
         instance.content_type.model = "userstory"
         instance.content_object.subject = "test"
         result = render(dummy_project, "**#1**")
-        expected_result = '<p><strong><a alt="test" class="reference user-story" href="http://localhost:9001/project/test/us/1" title="test">&num;1</a></strong></p>'
+        expected_result = '<p><strong><a alt="test" class="reference user-story" href="http://localhost:9001/project/test/us/1" title="test">#1</a></strong></p>'
         assert result == expected_result
 
 
@@ -53,7 +53,7 @@ def test_proccessor_valid_issue_reference():
         instance.content_type.model = "issue"
         instance.content_object.subject = "test"
         result = render(dummy_project, "**#2**")
-        expected_result = '<p><strong><a alt="test" class="reference issue" href="http://localhost:9001/project/test/issue/2" title="test">&num;2</a></strong></p>'
+        expected_result = '<p><strong><a alt="test" class="reference issue" href="http://localhost:9001/project/test/issue/2" title="test">#2</a></strong></p>'
         assert result == expected_result
 
 
@@ -63,7 +63,7 @@ def test_proccessor_valid_task_reference():
         instance.content_type.model = "task"
         instance.content_object.subject = "test"
         result = render(dummy_project, "**#3**")
-        expected_result = '<p><strong><a alt="test" class="reference task" href="http://localhost:9001/project/test/task/3" title="test">&num;3</a></strong></p>'
+        expected_result = '<p><strong><a alt="test" class="reference task" href="http://localhost:9001/project/test/task/3" title="test">#3</a></strong></p>'
         assert result == expected_result
 
 
@@ -140,20 +140,20 @@ def test_render_url_automail():
 
 
 def test_render_absolute_image():
-    assert render(dummy_project, "![test](/test.png)") == "<p><img alt=\"test\" src=\"/test.png\" /></p>"
+    assert render(dummy_project, "![test](/test.png)") == "<p><img alt=\"test\" src=\"/test.png\"></p>"
 
 
 def test_render_relative_image():
-    assert render(dummy_project, "![test](test.png)") == "<p><img alt=\"test\" src=\"test.png\" /></p>"
+    assert render(dummy_project, "![test](test.png)") == "<p><img alt=\"test\" src=\"test.png\"></p>"
 
 
 def test_render_triple_quote_code():
-    expected_result = "<div class=\"codehilite\"><pre><span class=\"n\">print</span><span class=\"p\">(</span><span class=\"s\">&quot;test&quot;</span><span class=\"p\">)</span>\n</pre></div>"
+    expected_result = "<div class=\"codehilite\"><pre><span class=\"n\">print</span><span class=\"p\">(</span><span class=\"s\">\"test\"</span><span class=\"p\">)</span>\n</pre></div>"
     assert render(dummy_project, "```\nprint(\"test\")\n```") == expected_result
 
 
 def test_render_triple_quote_and_lang_code():
-    expected_result = "<div class=\"codehilite\"><pre><span class=\"k\">print</span><span class=\"p\">(</span><span class=\"s\">&quot;test&quot;</span><span class=\"p\">)</span>\n</pre></div>"
+    expected_result = "<div class=\"codehilite\"><pre><span class=\"k\">print</span><span class=\"p\">(</span><span class=\"s\">\"test\"</span><span class=\"p\">)</span>\n</pre></div>"
     assert render(dummy_project, "```python\nprint(\"test\")\n```") == expected_result