diff --git a/src/checkmk/constants-service.conf b/src/checkmk/constants-service.conf
index 73978a6..0ba9409 100644
--- a/src/checkmk/constants-service.conf
+++ b/src/checkmk/constants-service.conf
@@ -20,7 +20,7 @@ LXC_UNPRIVILEGED="1"
 LXC_NESTING="1"
 
 # checkmk version
-CMK_VERSION=2.1.0p19
+CMK_VERSION=2.1.0p21
 # build number of the debian package (needs to start with underscore)
 CMK_BUILD=_0