diff --git a/requirements.freeze.txt b/requirements.freeze.txt
index d9a8dfb581..a351182ebf 100644
--- a/requirements.freeze.txt
+++ b/requirements.freeze.txt
@@ -58,7 +58,7 @@ opentype-feature-freezer==1.30.0
 opentype-sanitizer==8.0.0.post2
 Parsley==1.3
 pathspec==0.8.0
-protobuf==3.15.0
+protobuf==3.18.3
 psautohint==2.0.0
 pycares==4.2.0
 pyclipper==1.1.0.post1