diff --git a/tools/releasetools/validate_target_files.py b/tools/releasetools/validate_target_files.py
index acd5b6e..886de26 100755
--- a/tools/releasetools/validate_target_files.py
+++ b/tools/releasetools/validate_target_files.py
@@ -90,6 +90,12 @@
         logging.warning('Skipping %s that has incomplete block list', entry)
         continue
 
+      # TODO(b/79951650): Handle files with non-monotonic ranges.
+      if not ranges.monotonic:
+        logging.warning(
+            'Skipping %s that has non-monotonic ranges: %s', entry, ranges)
+        continue
+
       blocks_sha1 = image.RangeSha1(ranges)
 
       # The filename under unpacked directory, such as SYSTEM/bin/sh.