diff --git a/src/test/fuzz/autofile.cpp b/src/test/fuzz/autofile.cpp
index bf7119b761c..45316b6b218 100644
--- a/src/test/fuzz/autofile.cpp
+++ b/src/test/fuzz/autofile.cpp
@@ -2,16 +2,16 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <span.h>
 #include <streams.h>
 #include <test/fuzz/FuzzedDataProvider.h>
 #include <test/fuzz/fuzz.h>
 #include <test/fuzz/util.h>
 
 #include <array>
-#include <cstdint>
+#include <cstddef>
+#include <cstdio>
 #include <iostream>
-#include <optional>
-#include <string>
 #include <vector>
 
 FUZZ_TARGET(autofile)
@@ -20,6 +20,7 @@ FUZZ_TARGET(autofile)
     FuzzedFileProvider fuzzed_file_provider{fuzzed_data_provider};
     AutoFile auto_file{
         fuzzed_file_provider.open(),
+        ConsumeRandomLengthByteVector<std::byte>(fuzzed_data_provider),
     };
     LIMITED_WHILE(fuzzed_data_provider.ConsumeBool(), 100)
     {
diff --git a/src/test/fuzz/buffered_file.cpp b/src/test/fuzz/buffered_file.cpp
index e345aa301c7..813af63738b 100644
--- a/src/test/fuzz/buffered_file.cpp
+++ b/src/test/fuzz/buffered_file.cpp
@@ -2,16 +2,17 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#include <span.h>
 #include <streams.h>
 #include <test/fuzz/FuzzedDataProvider.h>
 #include <test/fuzz/fuzz.h>
 #include <test/fuzz/util.h>
 
 #include <array>
+#include <cstddef>
 #include <cstdint>
 #include <iostream>
 #include <optional>
-#include <string>
 #include <vector>
 
 FUZZ_TARGET(buffered_file)
@@ -19,7 +20,11 @@ FUZZ_TARGET(buffered_file)
     FuzzedDataProvider fuzzed_data_provider{buffer.data(), buffer.size()};
     FuzzedFileProvider fuzzed_file_provider{fuzzed_data_provider};
     std::optional<BufferedFile> opt_buffered_file;
-    CAutoFile fuzzed_file{fuzzed_file_provider.open(), 0};
+    CAutoFile fuzzed_file{
+        fuzzed_file_provider.open(),
+        0,
+        ConsumeRandomLengthByteVector<std::byte>(fuzzed_data_provider),
+    };
     try {
         opt_buffered_file.emplace(fuzzed_file, fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096), fuzzed_data_provider.ConsumeIntegralInRange<uint64_t>(0, 4096));
     } catch (const std::ios_base::failure&) {