diff --git a/libutils/BlobCache.cpp b/libutils/BlobCache.cpp
index f00bf14..8edb401 100644
--- a/libutils/BlobCache.cpp
+++ b/libutils/BlobCache.cpp
@@ -213,7 +213,14 @@
         memcpy(eheader->mData, keyBlob->getData(), keySize);
         memcpy(eheader->mData + keySize, valueBlob->getData(), valueSize);
 
-        byteOffset += align4(entrySize);
+        size_t totalSize = align4(entrySize);
+        if (totalSize > entrySize) {
+            // We have padding bytes. Those will get written to storage, and contribute to the CRC,
+            // so make sure we zero-them to have reproducible results.
+            memset(eheader->mData + keySize + valueSize, 0, totalSize - entrySize);
+        }
+
+        byteOffset += totalSize;
     }
 
     return OK;