diff --git a/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java b/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
index 46e79c34c27475b35d88c27e30d92a12f217a139..0ad439283e0c074b5fac187391b063e7694b1051 100644
--- a/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
+++ b/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
@@ -200,7 +200,7 @@ public class HudsonPrivateSecurityRealm extends SecurityRealm {
                 if(data.startsWith(prefix))
                     return new Details(data.substring(prefix.length()));
             }
-            return new Details(pwd);
+            return new Details(Util.fixNull(pwd));
         }
 
         public boolean isEnabled() {