diff --git a/src/tiffcomposite_int.cpp b/src/tiffcomposite_int.cpp
index 6da7a964d2..8890ec47c8 100644
--- a/src/tiffcomposite_int.cpp
+++ b/src/tiffcomposite_int.cpp
@@ -1207,7 +1207,12 @@ namespace Exiv2 {
                                                   valueIdx,
                                                   dataIdx,
                                                   imageIdx);
-            assert(len <= 4);
+#ifndef SUPPRESS_WARNINGS
+            if (len > 4) {
+                EXV_ERROR << "Unexpected length in TiffDirectory::writeDirEntry(): len == "
+                          << len << ".\n";
+            }
+#endif
             if (len < 4) {
                 memset(buf, 0x0, 4);
                 ioWrapper.write(buf, 4 - len);
diff --git a/test/data/issue_1845_poc.jp2 b/test/data/issue_1845_poc.jp2
new file mode 100644
index 0000000000..035d629621
Binary files /dev/null and b/test/data/issue_1845_poc.jp2 differ
diff --git a/tests/bugfixes/github/test_issue_1845.py b/tests/bugfixes/github/test_issue_1845.py
new file mode 100644
index 0000000000..6332ab18fc
--- /dev/null
+++ b/tests/bugfixes/github/test_issue_1845.py
@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+
+from system_tests import CaseMeta, CopyTmpFiles, path
+@CopyTmpFiles("$data_path/issue_1845_poc.jp2")
+
+class TiffDirectoryWriteDirEntryAssert(metaclass=CaseMeta):
+    """
+    Regression test for the bug described in:
+    https://github.com/Exiv2/exiv2/issues/1845
+    """
+    url = "https://github.com/Exiv2/exiv2/issues/1845"
+
+    filename = path("$tmp_path/issue_1845_poc.jp2")
+    commands = ["$exiv2 -q -D +1 ad $filename"]
+    stderr = [""]
+    stdout = [""]
+    retval = [0]