diff --git a/builder/data/usr/bin/pwnlib b/builder/data/usr/bin/pwnlib
index bc29171..f8da0d8 100755
--- a/builder/data/usr/bin/pwnlib
+++ b/builder/data/usr/bin/pwnlib
@@ -177,7 +177,8 @@ EOF
 
   pkill wpa_supplicant
   pkill dnsmasq
-  kill "$(pgrep -f "decryption-webserver")"
+  pid="$(pgrep -f "decryption-webserver")"
+  [[ -n "$pid" ]] && kill "$pid"
 
   return 0
 }