diff --git a/src/applications/passphrase/view/PassphraseCredentialControl.php b/src/applications/passphrase/view/PassphraseCredentialControl.php
--- a/src/applications/passphrase/view/PassphraseCredentialControl.php
+++ b/src/applications/passphrase/view/PassphraseCredentialControl.php
@@ -50,7 +50,8 @@
     // credential. Populate it into the menu to allow them to save the form
     // without making any changes.
     $current_phid = $this->getValue();
-    if (strlen($current_phid) && empty($options_map[$current_phid])) {
+    if (phutil_nonempty_string($current_phid) &&
+        empty($options_map[$current_phid])) {
       $viewer = $this->getViewer();
 
       $current_name = null;
diff --git a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldPHIDs.php b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldPHIDs.php
--- a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldPHIDs.php
+++ b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldPHIDs.php
@@ -40,6 +40,9 @@
     // TODO: Clean this up.
 
     $result = array();
+    if ($value === null) {
+      return $this;
+    }
     if (!is_array($value)) {
       $value = json_decode($value, true);
       if (is_array($value)) {