diff --git a/Dockerfile b/Dockerfile
index 6ca1c25..4bac9e5 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -22,7 +22,7 @@ ARG MODSECNGX_VER=v1.0.3
 ARG LRC_VER=v0.1.29rc1
 ARG LRL_VER=v0.14rc1
 ARG NHG2M_VER=3.4
-ARG NNTLM_VER=master
+ARG NNTLM_VER=v1.19.3-beta.1
 
 ARG LIBOQS_VER=0.10.1
 ARG OQSPROVIDER_VER=0.6.1