diff --git a/src/add-ons/kernel/file_systems/packagefs/AttributeIndex.cpp b/src/add-ons/kernel/file_systems/packagefs/AttributeIndex.cpp
index 3488ce32a8..e93a43424a 100644
--- a/src/add-ons/kernel/file_systems/packagefs/AttributeIndex.cpp
+++ b/src/add-ons/kernel/file_systems/packagefs/AttributeIndex.cpp
@@ -379,8 +379,9 @@ AttributeIndex::InternalGetIterator()
 AbstractIndexIterator*
 AttributeIndex::InternalFind(const void* key, size_t length)
 {
-	if (key == NULL)
+	if (HasFixedKeyLength() && length != KeyLength())
 		return NULL;
+
 	Iterator* iterator = new(std::nothrow) Iterator;
 	if (iterator != NULL) {
 		if (!iterator->SetTo(this, TreeKey(key, length))) {