diff --git a/src/cursor.c b/src/cursor.c
index 5ec88a77..8e92297e 100644
--- a/src/cursor.c
+++ b/src/cursor.c
@@ -1701,7 +1701,9 @@ __hot csr_t cursor_seek(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data, MDBX_cur
 
   csr_t ret;
   ret.exact = false;
-  if (unlikely(key->iov_len < mc->clc->k.lmin || key->iov_len > mc->clc->k.lmax)) {
+  if (unlikely(key->iov_len < mc->clc->k.lmin ||
+               (key->iov_len > mc->clc->k.lmax &&
+                (mc->clc->k.lmin == mc->clc->k.lmax || MDBX_DEBUG || MDBX_FORCE_ASSERTIONS)))) {
     cASSERT(mc, !"Invalid key-size");
     ret.err = MDBX_BAD_VALSIZE;
     return ret;