python · picnixz · Mar 6, 2026 · Mar 2, 2026 · Mar 2, 2026 · Mar 2, 2026
diff --git a/Misc/NEWS.d/next/Library/2026-03-02-19-41-39.gh-issue-145376.OOzSOh.rst b/Misc/NEWS.d/next/Library/2026-03-02-19-41-39.gh-issue-145376.OOzSOh.rst
@@ -0,0 +1 @@
+Fix double free and null pointer dereference in unusual error scenarios in :mod:`md5module` and :mod:`hmacmodule`.
@@ -1378,7 +1378,6 @@ static void
 py_hmac_hinfo_ht_free(void *hinfo)
 {
     py_hmac_hinfo *entry = (py_hmac_hinfo *)hinfo;
-    assert(entry->display_name != NULL);
     if (--(entry->refcnt) == 0) {
         Py_CLEAR(entry->display_name);
         PyMem_Free(hinfo);
@@ -1477,7 +1476,8 @@ py_hmac_hinfo_ht_new(void)
             e->hashlib_name == NULL ? e->name : e->hashlib_name
         );
         if (value->display_name == NULL) {
-            PyMem_Free(value);
+            /* value is owned by the table (refcnt > 0), so
+               _Py_hashtable_destroy() will free it. */
             goto error;
         }
     }

@@ -87,7 +87,10 @@ static void
 MD5_dealloc(PyObject *op)
 {
     MD5object *ptr = _MD5object_CAST(op);
-    Hacl_Hash_MD5_free(ptr->hash_state);
+    if (ptr->hash_state != NULL) {
+        Hacl_Hash_MD5_free(ptr->hash_state);
+        ptr->hash_state = NULL;
+    }
     PyTypeObject *tp = Py_TYPE(op);
     PyObject_GC_UnTrack(ptr);
     PyObject_GC_Del(ptr);
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Fix double free and null pointer dereference in unusual error scenarios in :mod:`md5module` and :mod:`hmacmodule`.
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