diff --git a/semantic-text-similarity/requirements.txt b/semantic-text-similarity/requirements.txt
index 64f36c7..18b8f97 100644
--- a/semantic-text-similarity/requirements.txt
+++ b/semantic-text-similarity/requirements.txt
@@ -114,7 +114,7 @@ Markdown==3.2.1
 MarkupSafe==1.1.0
 matplotlib==3.0.2
 mccabe==0.6.1
-mistune==0.8.4
+mistune==2.0.3
 mkl-fft==1.0.6
 mkl-random==1.0.2
 mock==4.0.2