diff --git a/src/main/java/com/cloudbees/plugins/credentials/SecretBytes.java b/src/main/java/com/cloudbees/plugins/credentials/SecretBytes.java
index a624f05a1..6b5ffcb73 100644
--- a/src/main/java/com/cloudbees/plugins/credentials/SecretBytes.java
+++ b/src/main/java/com/cloudbees/plugins/credentials/SecretBytes.java
@@ -364,6 +364,9 @@ public SecretBytes convert(Class type, Object value) {
             if (value instanceof String) {
                 return SecretBytes.fromString((String) value);
             }
+            if (value instanceof SecretBytes) {
+                return (SecretBytes) value;
+            }
             throw new IllegalClassException(SecretBytes.class, value.getClass());
         }
     }