diff --git a/docs/requirements.txt b/docs/requirements.txt
index 2963a76..03bbfd9 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -99,9 +99,9 @@ sphinx==1.8.4 \
 pbr==5.1.2 \
     --hash=sha256:a7953f66e1f82e4b061f43096a4bcc058f7d3d41de9b94ac871770e8bdd831a2 \
     --hash=sha256:d717573351cfe09f49df61906cd272abaa759b3e91744396b804965ff7bff38b
-babel==2.6.0 \
-    --hash=sha256:6778d85147d5d85345c14a26aada5e478ab04e39b078b0745ee6870c2b5cf669 \
-    --hash=sha256:8cba50f48c529ca3fa18cf81fa9403be176d374ac4d60738b839122dfaaa3d23
+babel==2.9.1 \
+    --hash=sha256:ab49e12b91d937cd11f0b67cb259a57ab4ad2b59ac7a3b41d6c06c0ac5b0def9 \
+    --hash=sha256:bc0c176f9f6a994582230df350aa6e05ba2ebe4b3ac317eab29d9be5d2768da0
 six==1.12.0 \
     --hash=sha256:3350809f0555b11f552448330d0b52d5f24c91a322ea4a15ef22629740f3761c \
     --hash=sha256:d16a0141ec1a18405cd4ce8b4613101da75da0e9a7aec5bdd4fa804d0e0eba73