diff --git a/crypto/aligned_alloc.c b/crypto/aligned_alloc.c
index dcc2b406a2..f2eed13c6c 100644
--- a/crypto/aligned_alloc.c
+++ b/crypto/aligned_alloc.c
@@ -21,8 +21,9 @@ void *ossl_malloc_align(size_t num, size_t alignment, void **freeptr,
 
     *freeptr = NULL;
 
-    /* Ensure that alignment is a power of two */
-    if (alignment == 0 || (alignment & (alignment - 1)) != 0) {
+    /* Ensure that alignment is a power of two no larger than 65536 */
+    if (alignment == 0 || (alignment & (alignment - 1)) != 0
+        || alignment > 65536) {
         ossl_report_alloc_err_inv(file, line);
         return NULL;
     }
diff --git a/crypto/mem.c b/crypto/mem.c
index 681cecfadf..f772e6c461 100644
--- a/crypto/mem.c
+++ b/crypto/mem.c
@@ -233,8 +233,9 @@ void *CRYPTO_aligned_alloc(size_t num, size_t alignment, void **freeptr,
 {
     *freeptr = NULL;
 
-    /* Ensure that alignment is a power of two */
-    if (alignment == 0 || (alignment & (alignment - 1)) != 0) {
+    /* Ensure that alignment is a power of two no larger than 65536 */
+    if (alignment == 0 || (alignment & (alignment - 1)) != 0
+        || alignment > 65536) {
         ossl_report_alloc_err_inv(file, line);
         return NULL;
     }
diff --git a/doc/man3/OPENSSL_malloc.pod b/doc/man3/OPENSSL_malloc.pod
index 63b7cfd29c..5ddc6e4a6c 100644
--- a/doc/man3/OPENSSL_malloc.pod
+++ b/doc/man3/OPENSSL_malloc.pod
@@ -125,7 +125,7 @@ OPENSSL_zalloc() calls memset() to zero the memory before returning.
 OPENSSL_aligned_alloc() operates just as OPENSSL_malloc() does, but it
 allows for the caller to specify an alignment value, for instances in
 which the default alignment of malloc is insufficient for the caller's
-needs.  Note, the alignment value must be a power of 2.
+needs.  Note, the alignment value must be a power of 2 no larger than 65536.
 NOTE: the call to OPENSSL_aligned_alloc() accepts a 3rd argument, I<freeptr>
 which must point to a void pointer.  On some platforms, there is no available
 library call to obtain memory allocations with alignment greater than what
@@ -311,6 +311,9 @@ was built with C<OPENSSL_SMALL_FOOTPRINT> macro defined.  Consequently,
 the caller may need to fall back to a non-aligned memory allocation
 (and open-code the alignment routine if the alignment is a requirement).
 
+Before OpenSSL 4.0, the call to OPENSSL_aligned_alloc() did not have
+an explicit upper limit on the value of I<alignment>.
+
 =head1 COPYRIGHT
 
 Copyright 2016-2025 The OpenSSL Project Authors. All Rights Reserved.
diff --git a/test/mem_alloc_test.c b/test/mem_alloc_test.c
index 30c479cd80..98283121a6 100644
--- a/test/mem_alloc_test.c
+++ b/test/mem_alloc_test.c
@@ -173,6 +173,8 @@ static const struct array_aligned_alloc_vector {
 
     { 8, 8, 63, EXP_INVAL, EXP_INVAL },
     { 8, 8, 64, EXP_NONNULL, EXP_NONNULL },
+    { 3, 4, 65536, EXP_NONNULL, EXP_NONNULL },
+    { 8, 8, 131072, EXP_INVAL, EXP_INVAL },
     { SIZE_MAX / 8 + 9, 8, 64, EXP_NONNULL, EXP_INT_OF },
 
     /*