diff --git a/Dockerfile.m4 b/Dockerfile.m4
index 793c42f..b61a81a 100644
--- a/Dockerfile.m4
+++ b/Dockerfile.m4
@@ -121,7 +121,7 @@ RUN <<-EOF
 EOF
 
 # Build TurboVNC
-ARG TURBOVNC_TREEISH=3.1.1
+ARG TURBOVNC_TREEISH=3.1.3
 ARG TURBOVNC_REMOTE=https://github.com/TurboVNC/turbovnc.git
 WORKDIR /tmp/turbovnc/
 RUN <<-EOF