diff --git a/.travis/docs-requirements.txt b/.travis/docs-requirements.txt
index 9e6cbb7..1737c97 100644
--- a/.travis/docs-requirements.txt
+++ b/.travis/docs-requirements.txt
@@ -3,7 +3,7 @@ Markdown==2.6.10
 MarkupSafe==1.0
 backports_abc==0.5
 backports.ssl_match_hostname==3.5.0.1
-certifi==2017.11.5
+certifi==2022.12.7
 click==6.7
 livereload==2.5.1
 mkdocs==0.15.3