diff --git a/meta-digi-arm/recipes-bsp/trustfence-cst/trustfence-cst-native.inc b/meta-digi-arm/recipes-bsp/trustfence-cst/trustfence-cst-native.inc
index 8d437c2b7..dd11a8fd4 100644
--- a/meta-digi-arm/recipes-bsp/trustfence-cst/trustfence-cst-native.inc
+++ b/meta-digi-arm/recipes-bsp/trustfence-cst/trustfence-cst-native.inc
@@ -8,7 +8,7 @@ LICENSE = "CLOSED"
 DEPENDS = "openssl-native"
 
 SRC_URI = " \
-    file://cst-${PV}.tar.gz \
+    ${@base_conditional('TRUSTFENCE_SIGN', '1', 'file://cst-${PV}.tar.gz', '', d)} \
     file://0001-gen_auth_encrypted_data-reuse-existing-DEK-file.patch \
     file://0002-hab4_pki_tree.sh-automate-script.patch \
     file://0003-openssl_helper-use-dev-urandom-as-seed-source.patch \