diff --git a/docs/rtfd-requirements.txt b/docs/rtfd-requirements.txt
index d02c7aa..b7c8648 100644
--- a/docs/rtfd-requirements.txt
+++ b/docs/rtfd-requirements.txt
@@ -1,5 +1,5 @@
 attrs==19.1.0
-cffi==1.12.2
+cffi==1.14.6
 Sphinx==1.8.4
 sphinx-rtd-theme==0.4.3
 sphinxcontrib-websupport==1.1.0