diff --git a/Misc/NEWS.d/next/Library/2026-06-27-17-19-09.gh-issue-151126.huUyOM.rst b/Misc/NEWS.d/next/Library/2026-06-27-17-19-09.gh-issue-151126.huUyOM.rst
new file mode 100644
index 000000000000000..2e51fd45b595486
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-06-27-17-19-09.gh-issue-151126.huUyOM.rst
@@ -0,0 +1,2 @@
+Fix two crashes in :mod:`tkinter` and :mod:`socket` modules initialization
+under a memory pressure. Sets missing :exc:`MemoryError`.
diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index 137eba40a762c0a..8fa58d07096e30b 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -3574,7 +3574,7 @@ PyInit__tkinter(void)
 
     tcl_lock = PyThread_allocate_lock();
     if (tcl_lock == NULL)
-        return NULL;
+        return PyErr_NoMemory();
 
     m = PyModule_Create(&_tkintermodule);
     if (m == NULL)
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index c69a9cc04982729..97abd064ffd5e92 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -9288,6 +9288,7 @@ socket_exec(PyObject *m)
 #if defined(USE_GETHOSTBYNAME_LOCK)
     netdb_lock = PyThread_allocate_lock();
     if (netdb_lock == NULL) {
+        PyErr_NoMemory();
         goto error;
     }
 #endif