diff --git a/stix_shifter/requirements.txt b/stix_shifter/requirements.txt
index 4f0fbd800..9a876c04c 100644
--- a/stix_shifter/requirements.txt
+++ b/stix_shifter/requirements.txt
@@ -1,10 +1,10 @@
 adal==1.2.2
-antlr4-python3-runtime==4.8
+antlr4-python3-runtime==4.9.3
 boto3==1.17.20
 flask==2.0.2
 pyOpenSSL==20.0.1
 flatten_json==0.1.13
-python-dateutil==2.8.1
+python-dateutil==2.8.2
 requests_toolbelt==0.9.1
 stix2-patterns==1.3.2
 stix2-validator==1.1.2