diff --git a/Lib/test/seq_tests.py b/Lib/test/seq_tests.py
index 2416249..72f4845 100644
--- a/Lib/test/seq_tests.py
+++ b/Lib/test/seq_tests.py
@@ -5,6 +5,7 @@
 import unittest
 import sys
 import pickle
+from test import support
 
 # Various iterables
 # This is used for checking the constructor (here and in test_deque.py)
@@ -408,3 +409,7 @@
             lst2 = pickle.loads(pickle.dumps(lst, proto))
             self.assertEqual(lst2, lst)
             self.assertNotEqual(id(lst2), id(lst))
+
+    def test_free_after_iterating(self):
+        support.check_free_after_iterating(self, iter, self.type2test)
+        support.check_free_after_iterating(self, reversed, self.type2test)
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index b82f9cb..e124fab 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -2366,3 +2366,22 @@
                                      "memory allocations")
     import _testcapi
     return _testcapi.run_in_subinterp(code)
+
+
+def check_free_after_iterating(test, iter, cls, args=()):
+    class A(cls):
+        def __del__(self):
+            nonlocal done
+            done = True
+            try:
+                next(it)
+            except StopIteration:
+                pass
+
+    done = False
+    it = iter(A(*args))
+    # Issue 26494: Shouldn't crash
+    test.assertRaises(StopIteration, next, it)
+    # The sequence should be deallocated just after the end of iterating
+    gc_collect()
+    test.assertTrue(done)
diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index 80798f2..1bd3a1e 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -747,6 +747,10 @@
         self.assertRaisesRegex(TypeError, r'\bendswith\b', b.endswith,
                                 x, None, None, None)
 
+    def test_free_after_iterating(self):
+        test.support.check_free_after_iterating(self, iter, self.type2test)
+        test.support.check_free_after_iterating(self, reversed, self.type2test)
+
 
 class BytesTest(BaseBytesTest, unittest.TestCase):
     type2test = bytes
diff --git a/Lib/test/test_deque.py b/Lib/test/test_deque.py
index ec2be83..7041d17 100644
--- a/Lib/test/test_deque.py
+++ b/Lib/test/test_deque.py
@@ -905,6 +905,10 @@
         # For now, bypass tests that require slicing
         pass
 
+    def test_free_after_iterating(self):
+        # For now, bypass tests that require slicing
+        self.skipTest("Exhausted deque iterator doesn't free a deque")
+
 #==============================================================================
 
 libreftest = """
diff --git a/Lib/test/test_dict.py b/Lib/test/test_dict.py
index 3b42414..075cb5a 100644
--- a/Lib/test/test_dict.py
+++ b/Lib/test/test_dict.py
@@ -952,6 +952,12 @@
         d = {X(): 0, 1: 1}
         self.assertRaises(RuntimeError, d.update, other)
 
+    def test_free_after_iterating(self):
+        support.check_free_after_iterating(self, iter, dict)
+        support.check_free_after_iterating(self, lambda d: iter(d.keys()), dict)
+        support.check_free_after_iterating(self, lambda d: iter(d.values()), dict)
+        support.check_free_after_iterating(self, lambda d: iter(d.items()), dict)
+
 from test import mapping_tests
 
 class GeneralMappingTests(mapping_tests.BasicTestMappingProtocol):
diff --git a/Lib/test/test_iter.py b/Lib/test/test_iter.py
index 56e21f8..54ddbaa 100644
--- a/Lib/test/test_iter.py
+++ b/Lib/test/test_iter.py
@@ -3,6 +3,7 @@
 import sys
 import unittest
 from test.support import run_unittest, TESTFN, unlink, cpython_only
+from test.support import check_free_after_iterating
 import pickle
 import collections.abc
 
@@ -980,6 +981,9 @@
         self.assertEqual(next(it), 0)
         self.assertEqual(next(it), 1)
 
+    def test_free_after_iterating(self):
+        check_free_after_iterating(self, iter, SequenceClass, (0,))
+
 
 def test_main():
     run_unittest(TestCase)
diff --git a/Lib/test/test_ordered_dict.py b/Lib/test/test_ordered_dict.py
index 8ab0a9f..901d4b2 100644
--- a/Lib/test/test_ordered_dict.py
+++ b/Lib/test/test_ordered_dict.py
@@ -598,6 +598,12 @@
         gc.collect()
         self.assertIsNone(r())
 
+    def test_free_after_iterating(self):
+        support.check_free_after_iterating(self, iter, self.OrderedDict)
+        support.check_free_after_iterating(self, lambda d: iter(d.keys()), self.OrderedDict)
+        support.check_free_after_iterating(self, lambda d: iter(d.values()), self.OrderedDict)
+        support.check_free_after_iterating(self, lambda d: iter(d.items()), self.OrderedDict)
+
 
 class PurePythonOrderedDictTests(OrderedDictTests, unittest.TestCase):
 
diff --git a/Lib/test/test_set.py b/Lib/test/test_set.py
index 54de508..0b99dfc 100644
--- a/Lib/test/test_set.py
+++ b/Lib/test/test_set.py
@@ -362,6 +362,9 @@
         gc.collect()
         self.assertTrue(ref() is None, "Cycle was not collected")
 
+    def test_free_after_iterating(self):
+        support.check_free_after_iterating(self, iter, self.thetype)
+
 class TestSet(TestJointOps, unittest.TestCase):
     thetype = set
     basetype = set
diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index c30310e..c281146 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -2729,6 +2729,10 @@
                 # Check that the second call returns the same result
                 self.assertEqual(getargs_s_hash(s), chr(k).encode() * (i + 1))
 
+    def test_free_after_iterating(self):
+        support.check_free_after_iterating(self, iter, str)
+        support.check_free_after_iterating(self, reversed, str)
+
 
 class StringModuleTest(unittest.TestCase):
     def test_formatter_parser(self):
diff --git a/Misc/NEWS b/Misc/NEWS
index 59c0828..391bbf2 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,11 @@
 Core and Builtins
 -----------------
 
+- Issue #26494: Fixed crash on iterating exhausting iterators.
+  Affected classes are generic sequence iterators, iterators of str, bytes,
+  bytearray, list, tuple, set, frozenset, dict, OrderedDict, corresponding
+  views and os.scandir() iterator.
+
 - Issue #26581: If coding cookie is specified multiple times on a line in
   Python source code file, only the first one is taken to account.
 
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 710bcde..c95668b 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -11928,13 +11928,15 @@
 static void
 ScandirIterator_close(ScandirIterator *iterator)
 {
-    if (iterator->handle == INVALID_HANDLE_VALUE)
+    HANDLE handle = iterator->handle;
+
+    if (handle == INVALID_HANDLE_VALUE)
         return;
 
-    Py_BEGIN_ALLOW_THREADS
-    FindClose(iterator->handle);
-    Py_END_ALLOW_THREADS
     iterator->handle = INVALID_HANDLE_VALUE;
+    Py_BEGIN_ALLOW_THREADS
+    FindClose(handle);
+    Py_END_ALLOW_THREADS
 }
 
 static PyObject *
@@ -11984,13 +11986,15 @@
 static void
 ScandirIterator_close(ScandirIterator *iterator)
 {
-    if (!iterator->dirp)
+    DIR *dirp = iterator->dirp;
+
+    if (!dirp)
         return;
 
-    Py_BEGIN_ALLOW_THREADS
-    closedir(iterator->dirp);
-    Py_END_ALLOW_THREADS
     iterator->dirp = NULL;
+    Py_BEGIN_ALLOW_THREADS
+    closedir(dirp);
+    Py_END_ALLOW_THREADS
     return;
 }
 
diff --git a/Objects/bytearrayobject.c b/Objects/bytearrayobject.c
index c59ad24..c723a9c 100644
--- a/Objects/bytearrayobject.c
+++ b/Objects/bytearrayobject.c
@@ -3186,8 +3186,8 @@
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }
 
diff --git a/Objects/bytesobject.c b/Objects/bytesobject.c
index 51d0871..495c3eb 100644
--- a/Objects/bytesobject.c
+++ b/Objects/bytesobject.c
@@ -3628,8 +3628,8 @@
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }
 
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index e4dff98..d774586 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -2985,8 +2985,8 @@
     return key;
 
 fail:
-    Py_DECREF(d);
     di->di_dict = NULL;
+    Py_DECREF(d);
     return NULL;
 }
 
@@ -3066,8 +3066,8 @@
     return value;
 
 fail:
-    Py_DECREF(d);
     di->di_dict = NULL;
+    Py_DECREF(d);
     return NULL;
 }
 
@@ -3161,8 +3161,8 @@
     return result;
 
 fail:
-    Py_DECREF(d);
     di->di_dict = NULL;
+    Py_DECREF(d);
     return NULL;
 }
 
diff --git a/Objects/iterobject.c b/Objects/iterobject.c
index 2fb0c88..ab29ff8 100644
--- a/Objects/iterobject.c
+++ b/Objects/iterobject.c
@@ -69,8 +69,8 @@
         PyErr_ExceptionMatches(PyExc_StopIteration))
     {
         PyErr_Clear();
-        Py_DECREF(seq);
         it->it_seq = NULL;
+        Py_DECREF(seq);
     }
     return NULL;
 }
diff --git a/Objects/listobject.c b/Objects/listobject.c
index eee7c68..d688179 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -2782,8 +2782,8 @@
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }
 
@@ -2912,9 +2912,17 @@
 listreviter_next(listreviterobject *it)
 {
     PyObject *item;
-    Py_ssize_t index = it->it_index;
-    PyListObject *seq = it->it_seq;
+    Py_ssize_t index;
+    PyListObject *seq;
 
+    assert(it != NULL);
+    seq = it->it_seq;
+    if (seq == NULL) {
+        return NULL;
+    }
+    assert(PyList_Check(seq));
+
+    index = it->it_index;
     if (index>=0 && index < PyList_GET_SIZE(seq)) {
         item = PyList_GET_ITEM(seq, index);
         it->it_index--;
@@ -2922,10 +2930,8 @@
         return item;
     }
     it->it_index = -1;
-    if (seq != NULL) {
-        it->it_seq = NULL;
-        Py_DECREF(seq);
-    }
+    it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }
 
diff --git a/Objects/setobject.c b/Objects/setobject.c
index 582f280..4ef692d 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -839,8 +839,8 @@
     return key;
 
 fail:
-    Py_DECREF(so);
     si->si_set = NULL;
+    Py_DECREF(so);
     return NULL;
 }
 
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
index 7efa1a6..7920fec 100644
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -964,8 +964,8 @@
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }
 
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index adc4615..230125b 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -15149,8 +15149,8 @@
         return item;
     }
 
-    Py_DECREF(seq);
     it->it_seq = NULL;
+    Py_DECREF(seq);
     return NULL;
 }