diff --git a/cmake-tool/helpers/shoehorn.py b/cmake-tool/helpers/shoehorn.py
index 0bba19bb..9f759fd1 100755
--- a/cmake-tool/helpers/shoehorn.py
+++ b/cmake-tool/helpers/shoehorn.py
@@ -142,6 +142,7 @@ def main() -> int:
     rootservers = []
     is_dtb_present = False
     is_good_fit = False
+    kernel_elf = None
 
     with libarchive.memory_reader(get_cpio(image)) as archive:
         for entry in archive:
@@ -160,6 +161,9 @@ def main() -> int:
             else:
                 rootservers.append(get_bytes(entry))
 
+    if not kernel_elf:
+        die('missing kernel.elf')
+
     # Enumerate the regions as we encounter them for diagnostic purposes.
     region_counter = -1
     last_region = len(platform['memory'])