diff --git a/src/libbson b/src/libbson
index 20c7a1a4a..ca42366d1 160000
--- a/src/libbson
+++ b/src/libbson
@@ -1 +1 @@
-Subproject commit 20c7a1a4a8ab348a20ed2c6e47459795ef87e987
+Subproject commit ca42366d16a5c1fb33aacdf9fefadf4e98d7aaa3
diff --git a/src/libmongoc b/src/libmongoc
index 558731852..f09af3629 160000
--- a/src/libmongoc
+++ b/src/libmongoc
@@ -1 +1 @@
-Subproject commit 5587318521af01e603f8f92cad57cb42c27c03b9
+Subproject commit f09af36295435576eb5d6323cbe3cc62f465a0b7
diff --git a/tests/connect/bug1045.phpt b/tests/connect/bug1045.phpt
new file mode 100644
index 000000000..ab35b8e6e
--- /dev/null
+++ b/tests/connect/bug1045.phpt
@@ -0,0 +1,25 @@
+--TEST--
+PHPC-1045: Segfault if username is not provided for SCRAM-SHA-1 authMechanism
+--SKIPIF--
+<?php require __DIR__ . "/../utils/basic-skipif.inc"; ?>
+<?php NEEDS('STANDALONE'); CLEANUP(STANDALONE); ?>
+--FILE--
+<?php
+
+require_once __DIR__ . "/../utils/basic.inc";
+
+// STANDALONE does not support auth, but that is not necessary for the test
+$m = new MongoDB\Driver\Manager(STANDALONE, ['authMechanism' => 'SCRAM-SHA-1', 'ssl' => false]);
+
+// Execute a basic ping command to trigger connection initialization
+echo throws(function() use ($m) {
+    $m->executeCommand('admin', new MongoDB\Driver\Command(['ping'=>1]));
+}, 'MongoDB\Driver\Exception\RuntimeException'), "\n";
+
+?>
+===DONE===
+<?php exit(0); ?>
+--EXPECTF--
+OK: Got MongoDB\Driver\Exception\RuntimeException
+SCRAM Failure: username is not set
+===DONE===