diff --git a/Dockerfile b/Dockerfile
index 6ad82ba041..cb80a68b62 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,6 +1,6 @@
 # This Dockerfile is for testing only.
 
-FROM bpssysadmin/rt-base-debian:RT-6.0.0-bullseye-20240920
+FROM bpssysadmin/rt-base-debian:RT-6.0.0-buster-20241220
 
 ENV RT_TEST_PARALLEL 1
 ENV RT_TEST_DEVEL 1