diff --git a/requirements-dev.txt b/requirements-dev.txt
index b1b21ac30..c17b88a69 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -531,7 +531,7 @@ proto-plus==1.23.0
     #   -r requirements-tests.txt
     #   google-api-core
     #   google-cloud-private-ca
-protobuf==4.25.5
+protobuf==4.25.6
     # via
     #   -r requirements-tests.txt
     #   google-api-core
diff --git a/requirements-docs.txt b/requirements-docs.txt
index c1fd1fad9..bfe14d158 100644
--- a/requirements-docs.txt
+++ b/requirements-docs.txt
@@ -549,7 +549,7 @@ proto-plus==1.23.0
     #   -r requirements-tests.txt
     #   google-api-core
     #   google-cloud-private-ca
-protobuf==4.25.5
+protobuf==4.25.6
     # via
     #   -r requirements-tests.txt
     #   google-api-core
diff --git a/requirements-tests.txt b/requirements-tests.txt
index b6fee073e..33a30f38c 100644
--- a/requirements-tests.txt
+++ b/requirements-tests.txt
@@ -431,7 +431,7 @@ proto-plus==1.23.0
     #   -r requirements.txt
     #   google-api-core
     #   google-cloud-private-ca
-protobuf==4.25.5
+protobuf==4.25.6
     # via
     #   -r requirements.txt
     #   google-api-core
diff --git a/requirements.txt b/requirements.txt
index cf0d07847..4844f4256 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -235,7 +235,7 @@ proto-plus==1.23.0
     # via
     #   google-api-core
     #   google-cloud-private-ca
-protobuf==4.25.5
+protobuf==4.25.6
     # via
     #   -r requirements.in
     #   google-api-core