diff --git a/src/core/connection.c b/src/core/connection.c
index 490d742d46..bdb505593b 100644
--- a/src/core/connection.c
+++ b/src/core/connection.c
@@ -692,11 +692,14 @@ QuicConnIndicateEvent(
         // MsQuic shouldn't indicate reentrancy to the app when at all possible.
         // The general exception to this rule is when the connection is being
         // closed because the API MUST block until all work is completed, so we
-        // have to execute the event callbacks inline.
+        // have to execute the event callbacks inline. Custom executions always
+        // have InlineApiExecution set, which makes this reentrancy check
+        // unreliable, so it is skipped for custom executions.
         //
         CXPLAT_DBG_ASSERT(
             !Connection->State.InlineApiExecution ||
-            Connection->State.HandleClosed);
+            Connection->State.HandleClosed ||
+            MsQuicLib.CustomExecutions);
         Status =
             Connection->ClientCallbackHandler(
                 (HQUIC)Connection,
diff --git a/src/core/stream.c b/src/core/stream.c
index 350dcb557e..ec426b406c 100644
--- a/src/core/stream.c
+++ b/src/core/stream.c
@@ -470,13 +470,16 @@ QuicStreamIndicateEvent(
         // or stream is being closed because the API MUST block until all work
         // is completed, so we have to execute the event callbacks inline. There
         // is also one additional exception for start complete when StreamStart
-        // is called synchronously on an MsQuic thread.
+        // is called synchronously on an MsQuic thread. Custom executions
+        // always have InlineApiExecution set, which makes this reentrancy
+        // check unreliable, so it is skipped for custom executions.
         //
         CXPLAT_DBG_ASSERT(
             !Stream->Connection->State.InlineApiExecution ||
             Stream->Connection->State.HandleClosed ||
             Stream->Flags.HandleClosed ||
-            Event->Type == QUIC_STREAM_EVENT_START_COMPLETE);
+            Event->Type == QUIC_STREAM_EVENT_START_COMPLETE ||
+            MsQuicLib.CustomExecutions);
         Status =
             Stream->ClientCallbackHandler(
                 (HQUIC)Stream,