diff --git a/.dockerignore b/.dockerignore
index f9fbc56056..1787a70c01 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -4,3 +4,4 @@
 appveyor.yml
 build
 circle.yml
+/vndr.log
diff --git a/.gitignore b/.gitignore
index 59cec00b21..a1f1bc9daf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,3 +16,4 @@ cli/winresources/rsrc_amd64.syso
 /docs/yaml/gen/
 coverage.txt
 profile.out
+/vndr.log
diff --git a/Makefile b/Makefile
index 656cfb856d..96c6379c93 100644
--- a/Makefile
+++ b/Makefile
@@ -64,8 +64,9 @@ dynbinary: ## build dynamically linked binary
 
 vendor: vendor.conf ## check that vendor matches vendor.conf
 	rm -rf vendor
-	bash -c 'vndr |& grep -v -i clone'
+	bash -c 'vndr |& grep -v -i clone | tee ./vndr.log'
 	scripts/validate/check-git-diff vendor
+	scripts/validate/check-all-packages-vendored
 
 .PHONY: authors
 authors: ## generate AUTHORS file from git history
diff --git a/scripts/validate/check-all-packages-vendored b/scripts/validate/check-all-packages-vendored
new file mode 100755
index 0000000000..f884c1f58d
--- /dev/null
+++ b/scripts/validate/check-all-packages-vendored
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+set -eu
+
+WARN_MISS_VENDOR='WARNING: dependency is not vendored'
+
+if grep -q "$WARN_MISS_VENDOR" "./vndr.log"; then
+	echo 
+	echo "Some dependencies are not vendored."
+	echo
+	exit 1
+fi