diff --git a/requirements-dev.txt b/requirements-dev.txt
index 0c9bbaa0e..98196e1e6 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 00d2f1549..4134660f2 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 192659ea4..ba0370bcf 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 21c52165c..37148497c 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