diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 0dad67390..1271b0db8 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -67,7 +67,6 @@ test-mutter:
     G_SLICE: "always-malloc"
     MALLOC_CHECK_: "3"
     NO_AT_BRIDGE: "1"
-    MALLOC_PERTURB_: "123"
   script:
     - dconf update
     - mkdir -m 700 $XDG_RUNTIME_DIR