diff --git a/LibreNMS/Authentication/ActiveDirectoryCommon.php b/LibreNMS/Authentication/ActiveDirectoryCommon.php
index 47d2925259..2fd436d48b 100644
--- a/LibreNMS/Authentication/ActiveDirectoryCommon.php
+++ b/LibreNMS/Authentication/ActiveDirectoryCommon.php
@@ -196,7 +196,7 @@ trait ActiveDirectoryCommon
         ];
     }
 
-    public function getUser($user_id)
+    public function getUser($user_id): array
     {
         $connection = $this->getConnection();
         $domain_sid = $this->getDomainSid();
@@ -204,16 +204,19 @@ trait ActiveDirectoryCommon
         $search_filter = "(&(objectcategory=person)(objectclass=user)(objectsid=$domain_sid-$user_id))";
         $attributes = ['samaccountname', 'displayname', 'objectsid', 'mail'];
         $search = ldap_search($connection, Config::get('auth_ad_base_dn'), $search_filter, $attributes);
-        $entry = ldap_get_entries($connection, $search);
 
-        if (isset($entry[0]['samaccountname'][0])) {
-            return $this->userFromAd($entry[0]);
+        if ($search !== false) {
+            $entry = ldap_get_entries($connection, $search);
+
+            if (isset($entry[0]['samaccountname'][0])) {
+                return $this->userFromAd($entry[0]);
+            }
         }
 
         return [];
     }
 
-    protected function getDomainSid()
+    protected function getDomainSid(): string
     {
         $connection = $this->getConnection();
 
@@ -226,6 +229,13 @@ trait ActiveDirectoryCommon
             '(objectClass=*)',
             ['objectsid']
         );
+
+        if ($search === false) {
+            \Log::debug('AD Auth: Could not determine domain SID');
+
+            return '';
+        }
+
         $entry = ldap_get_entries($connection, $search);
 
         return substr($this->sidFromLdap($entry[0]['objectsid'][0]), 0, 41);
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index cb04009028..aa2d4cb308 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -1005,11 +1005,6 @@ parameters:
 			count: 1
 			path: LibreNMS/Authentication/ADAuthorizationAuthorizer.php
 
-		-
-			message: "#^Method LibreNMS\\\\Authentication\\\\ADAuthorizationAuthorizer\\:\\:getDomainSid\\(\\) has no return type specified\\.$#"
-			count: 1
-			path: LibreNMS/Authentication/ADAuthorizationAuthorizer.php
-
 		-
 			message: "#^Method LibreNMS\\\\Authentication\\\\ADAuthorizationAuthorizer\\:\\:getFullname\\(\\) has no return type specified\\.$#"
 			count: 1
@@ -1125,11 +1120,6 @@ parameters:
 			count: 1
 			path: LibreNMS/Authentication/ActiveDirectoryAuthorizer.php
 
-		-
-			message: "#^Method LibreNMS\\\\Authentication\\\\ActiveDirectoryAuthorizer\\:\\:getDomainSid\\(\\) has no return type specified\\.$#"
-			count: 1
-			path: LibreNMS/Authentication/ActiveDirectoryAuthorizer.php
-
 		-
 			message: "#^Method LibreNMS\\\\Authentication\\\\ActiveDirectoryAuthorizer\\:\\:getFullname\\(\\) has no return type specified\\.$#"
 			count: 1