diff --git a/Gemfile b/Gemfile
index d27bc276088c873aa70a2bec8d97e27535ac8ccb..9bd1b0a02a1a3035355ff5bf598343c0df9b8738 100644
--- a/Gemfile
+++ b/Gemfile
@@ -139,7 +139,7 @@ gem 'html-pipeline', '~> 2.8'
 gem 'deckar01-task_list', '2.2.1'
 gem 'gitlab-markup', '~> 1.7.0'
 gem 'github-markup', '~> 1.7.0', require: 'github/markup'
-gem 'commonmarker', '~> 0.17'
+gem 'commonmarker', '~> 0.20'
 gem 'RedCloth', '~> 4.3.2'
 gem 'rdoc', '~> 6.0'
 gem 'org-ruby', '~> 0.9.12'
diff --git a/Gemfile.lock b/Gemfile.lock
index 15465cd6b03a1f0888c19531aa900f25e5f93d4b..b641f1f48beb1db4a8214e60bc81d4ec9fd36308 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -157,7 +157,7 @@ GEM
     coercible (1.0.0)
       descendants_tracker (~> 0.0.1)
     colored2 (3.1.2)
-    commonmarker (0.17.13)
+    commonmarker (0.20.1)
       ruby-enum (~> 0.5)
     concord (0.1.5)
       adamantium (~> 0.2.0)
@@ -1146,7 +1146,7 @@ DEPENDENCIES
   carrierwave (~> 1.3)
   charlock_holmes (~> 0.7.5)
   chronic (~> 0.10.2)
-  commonmarker (~> 0.17)
+  commonmarker (~> 0.20)
   concurrent-ruby (~> 1.1)
   connection_pool (~> 2.0)
   countries (~> 3.0)
diff --git a/lib/banzai/filter/markdown_engines/common_mark.rb b/lib/banzai/filter/markdown_engines/common_mark.rb
index d3af776db05ebafce6688f440bf85b4138402faf..7be52fc497f211a580a755bbac629d358a0175e2 100644
--- a/lib/banzai/filter/markdown_engines/common_mark.rb
+++ b/lib/banzai/filter/markdown_engines/common_mark.rb
@@ -29,7 +29,9 @@ class CommonMark
         # If in the future the syntax is about to be made GitHub-compatible, please, add `:GITHUB_PRE_LANG` render option below
         # and remove `code_block` method from `lib/banzai/renderer/common_mark/html.rb`.
         RENDER_OPTIONS = [
-          :DEFAULT # default rendering system. Nothing special.
+          # as of commonmarker 0.18.0, we need to use :UNSAFE to get the same as the original :DEFAULT
+          # https://github.com/gjtorikian/commonmarker/pull/81
+          :UNSAFE
         ].freeze
 
         RENDER_OPTIONS_SOURCEPOS = RENDER_OPTIONS + [