diff --git a/helio b/helio
index 05c316e171e3..2ab4412b78af 160000
--- a/helio
+++ b/helio
@@ -1 +1 @@
-Subproject commit 05c316e171e31a6f23165b426b7caf0174f90838
+Subproject commit 2ab4412b78afbf7d3102b472fb0e6f70b194a535
diff --git a/src/core/dash.h b/src/core/dash.h
index de7a025d44d3..09dad365b4a5 100644
--- a/src/core/dash.h
+++ b/src/core/dash.h
@@ -954,12 +954,13 @@ auto DashTable<_Key, _Value, Policy>::GetRandomCursor(absl::BitGen* bitgen) -> C
 template <typename _Key, typename _Value, typename Policy>
 template <typename Cb>
 auto DashTable<_Key, _Value, Policy>::Traverse(Cursor curs, Cb&& cb) -> Cursor {
-  if (curs.bucket_id() >= Policy::kBucketNum)  // sanity.
-    return 0;
-
   uint32_t sid = curs.segment_id(global_depth_);
   uint8_t bid = curs.bucket_id();
 
+  // Test validity of the cursor.
+  if (bid >= Policy::kBucketNum || sid >= segment_.size())
+    return 0;
+
   auto hash_fun = [this](const auto& k) { return policy_.HashFn(k); };
 
   bool fetched = false;
diff --git a/src/server/generic_family_test.cc b/src/server/generic_family_test.cc
index 68d54ea6f82c..e2c1ed605ed8 100644
--- a/src/server/generic_family_test.cc
+++ b/src/server/generic_family_test.cc
@@ -872,4 +872,9 @@ TEST_F(GenericFamilyTest, RestoreOOM) {
   EXPECT_THAT(resp, ErrArg("Out of memory"));
 }
 
+TEST_F(GenericFamilyTest, Bug4466) {
+  auto resp = Run({"SCAN","9223372036854775808"});  // an invalid cursor should not crash us.
+  EXPECT_THAT(resp, RespElementsAre("0", RespElementsAre()));
+}
+
 }  // namespace dfly
diff --git a/src/server/script_mgr.cc b/src/server/script_mgr.cc
index 0053a02f470f..ee29617a7d1c 100644
--- a/src/server/script_mgr.cc
+++ b/src/server/script_mgr.cc
@@ -43,6 +43,7 @@ ABSL_FLAG(
     std::vector<std::string>({
         "351130589c64523cb98978dc32c64173a31244f3",  // Sidekiq, see #2442
         "6ae15ef4678593dc61f991c9953722d67d822776",  // Sidekiq, see #2442
+        "34b1048274c8e50a0cc587a3ed9c383a82bb78c5"   // Sidekiq
     }),
     "Comma-separated list of Lua script SHAs which are allowed to access undeclared keys. SHAs are "
     "only looked at when loading the script, and new values do not affect already-loaded script.");