diff --git a/Gemfile b/Gemfile
index 412f6f42e08..01ec5a23f72 100644
--- a/Gemfile
+++ b/Gemfile
@@ -53,7 +53,7 @@ gem 'browser', '~> 2.2'
 
 # Extracting information from a git repository
 # Provide access to Gitlab::Git library
-gem 'gitlab_git', '~> 10.6.3'
+gem 'gitlab_git', '~> 10.6.6'
 
 # LDAP Auth
 # GitLab fork with several improvements to original library. For full list of changes
diff --git a/Gemfile.lock b/Gemfile.lock
index c559d09718b..cecd87e2e2b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -279,7 +279,7 @@ GEM
       diff-lcs (~> 1.1)
       mime-types (>= 1.16, < 3)
       posix-spawn (~> 0.3)
-    gitlab_git (10.6.3)
+    gitlab_git (10.6.6)
       activesupport (~> 4.0)
       charlock_holmes (~> 0.7.3)
       github-linguist (~> 4.7.0)
@@ -401,7 +401,7 @@ GEM
       mime-types (>= 1.16, < 4)
     mail_room (0.8.0)
     method_source (0.8.2)
-    mime-types (2.99.2)
+    mime-types (2.99.3)
     mimemagic (0.3.0)
     mini_portile2 (2.1.0)
     minitest (5.7.0)
@@ -866,7 +866,7 @@ DEPENDENCIES
   github-linguist (~> 4.7.0)
   github-markup (~> 1.4)
   gitlab-flowdock-git-hook (~> 1.0.1)
-  gitlab_git (~> 10.6.3)
+  gitlab_git (~> 10.6.6)
   gitlab_meta (= 7.0)
   gitlab_omniauth-ldap (~> 1.2.1)
   gollum-lib (~> 4.2)
diff --git a/app/models/blob.rb b/app/models/blob.rb
index 12cc5aaafba..ab92e820335 100644
--- a/app/models/blob.rb
+++ b/app/models/blob.rb
@@ -22,6 +22,18 @@ class Blob < SimpleDelegator
     new(blob)
   end
 
+  # Returns the data of the blob.
+  #
+  # If the blob is a text based blob the content is converted to UTF-8 and any
+  # invalid byte sequences are replaced.
+  def data
+    if binary?
+      super
+    else
+      @data ||= super.encode(Encoding::UTF_8, invalid: :replace, undef: :replace)
+    end
+  end
+
   def no_highlighting?
     size && size > 1.megabyte
   end
diff --git a/spec/models/blob_spec.rb b/spec/models/blob_spec.rb
index cee20234e1f..03d02b4d382 100644
--- a/spec/models/blob_spec.rb
+++ b/spec/models/blob_spec.rb
@@ -1,3 +1,4 @@
+# encoding: utf-8
 require 'rails_helper'
 
 describe Blob do
@@ -7,6 +8,25 @@ describe Blob do
     end
   end
 
+  describe '#data' do
+    context 'using a binary blob' do
+      it 'returns the data as-is' do
+        data = "\n\xFF\xB9\xC3"
+        blob = described_class.new(double(binary?: true, data: data))
+
+        expect(blob.data).to eq(data)
+      end
+    end
+
+    context 'using a text blob' do
+      it 'converts the data to UTF-8' do
+        blob = described_class.new(double(binary?: false, data: "\n\xFF\xB9\xC3"))
+
+        expect(blob.data).to eq("\n���")
+      end
+    end
+  end
+
   describe '#svg?' do
     it 'is falsey when not text' do
       git_blob = double(text?: false)