diff --git a/requirements/py2_cdeep3m_reqs.txt b/requirements/py2_cdeep3m_reqs.txt
index febced2..f05984e 100644
--- a/requirements/py2_cdeep3m_reqs.txt
+++ b/requirements/py2_cdeep3m_reqs.txt
@@ -21,7 +21,7 @@ pexpect==4.7.0
 pickleshare==0.7.5
 Pillow==6.1.0
 prompt-toolkit==1.0.16
-protobuf==3.9.1
+protobuf==3.15.0
 ptyprocess==0.6.0
 Pygments==2.4.2
 pyparsing==2.4.2
diff --git a/requirements/py3_cdeep3m_reqs.txt b/requirements/py3_cdeep3m_reqs.txt
index f54b8d4..15ecbb5 100644
--- a/requirements/py3_cdeep3m_reqs.txt
+++ b/requirements/py3_cdeep3m_reqs.txt
@@ -14,7 +14,7 @@ numpy==1.16.3
 opencv-contrib-python==4.1.0.25
 opencv-python==4.1.0.25
 Pillow==6.1.0
-protobuf==3.9.1
+protobuf==3.15.0
 ptyprocess==0.6.0
 Pygments==2.4.2
 pyparsing==2.4.2