diff --git a/cpython_sanity-3.14tsan/update.sh b/cpython_sanity-3.14tsan/update.sh
index c2fde976..a869a859 100755
--- a/cpython_sanity-3.14tsan/update.sh
+++ b/cpython_sanity-3.14tsan/update.sh
@@ -1,2 +1,3 @@
 #!/bin/sh
+sudo sysctl vm.mmap_rnd_bits=28
 docker pull ghcr.io/nascheme/cpython-tsan:3.14t