diff --git a/ci/requirements-docs.txt b/ci/requirements-docs.txt
index 1b252ba..5781815 100644
--- a/ci/requirements-docs.txt
+++ b/ci/requirements-docs.txt
@@ -8,7 +8,7 @@ alabaster==0.7.12
     # via sphinx
 babel==2.9.1
     # via sphinx
-certifi==2019.3.9
+certifi==2023.7.22
     # via requests
 chardet==3.0.4
     # via requests