diff --git a/doc/whatsnew/fragments/8740.bugfix b/doc/whatsnew/fragments/8740.bugfix
new file mode 100644
index 0000000000..dfa0d24929
--- /dev/null
+++ b/doc/whatsnew/fragments/8740.bugfix
@@ -0,0 +1,3 @@
+Fix a crash when ``__all__`` exists but cannot be inferred.
+
+Closes #8740
diff --git a/pylint/checkers/variables.py b/pylint/checkers/variables.py
index 2bd553fa11..4da52f6764 100644
--- a/pylint/checkers/variables.py
+++ b/pylint/checkers/variables.py
@@ -3046,7 +3046,10 @@ def _check_module_attrs(
     def _check_all(
         self, node: nodes.Module, not_consumed: dict[str, list[nodes.NodeNG]]
     ) -> None:
-        assigned = next(node.igetattr("__all__"))
+        try:
+            assigned = next(node.igetattr("__all__"))
+        except astroid.InferenceError:
+            return
         if isinstance(assigned, util.UninferableBase):
             return
         if assigned.pytype() not in {"builtins.list", "builtins.tuple"}:
diff --git a/tests/functional/u/undefined/undefined_all_variable_edge_case.py b/tests/functional/u/undefined/undefined_all_variable_edge_case.py
new file mode 100644
index 0000000000..647025f8d6
--- /dev/null
+++ b/tests/functional/u/undefined/undefined_all_variable_edge_case.py
@@ -0,0 +1,5 @@
+"""Edge case: __all__ exists in module's locals, but cannot be inferred.
+
+Other tests for undefined-all-variable in tests/functional/n/names_in__all__.py"""
+
+__all__ += []  # [undefined-variable]
diff --git a/tests/functional/u/undefined/undefined_all_variable_edge_case.txt b/tests/functional/u/undefined/undefined_all_variable_edge_case.txt
new file mode 100644
index 0000000000..54202984b6
--- /dev/null
+++ b/tests/functional/u/undefined/undefined_all_variable_edge_case.txt
@@ -0,0 +1 @@
+undefined-variable:5:0:5:7::Undefined variable '__all__':UNDEFINED