diff --git a/CMakeLists.txt b/CMakeLists.txt
index d55b97cfc..2854467fd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -287,7 +287,7 @@ set(GNSSSDR_GNSS_SIM_LOCAL_VERSION "master")
 set(GNSSSDR_GPSTK_LOCAL_VERSION "2.12")
 set(GNSSSDR_MATIO_LOCAL_VERSION "1.5.17")
 set(GNSSSDR_PUGIXML_LOCAL_VERSION "1.10")
-set(GNSSSDR_PROTOCOLBUFFERS_LOCAL_VERSION "3.11.3")
+set(GNSSSDR_PROTOCOLBUFFERS_LOCAL_VERSION "3.11.4")
 
 if(CMAKE_VERSION VERSION_LESS "3.0.2")
     set(GNSSSDR_GFLAGS_LOCAL_VERSION "2.2.1")  # Fix for CentOS 7
diff --git a/README.md b/README.md
index ab2467609..4c35efc8a 100644
--- a/README.md
+++ b/README.md
@@ -311,9 +311,9 @@ $ sudo apt-get install autoconf automake libtool curl make g++ unzip
 and then:
 
 ~~~~~~
-$ wget https://github.com/protocolbuffers/protobuf/releases/download/v3.11.3/protobuf-cpp-3.11.3.tar.gz
-$ tar xvfz protobuf-cpp-3.11.3.tar.gz
-$ cd protobuf-3.11.3
+$ wget https://github.com/protocolbuffers/protobuf/releases/download/v3.11.4/protobuf-cpp-3.11.4.tar.gz
+$ tar xvfz protobuf-cpp-3.11.4.tar.gz
+$ cd protobuf-3.11.4
 $ ./autogen.sh
 $ ./configure
 $ make