diff --git a/.changes/shell-execute-return.md b/.changes/shell-execute-return.md
new file mode 100644
index 00000000..6bc270f5
--- /dev/null
+++ b/.changes/shell-execute-return.md
@@ -0,0 +1,5 @@
+---
+"shell": "patch"
+---
+
+Fix a regression introduce in the last release where The JS API `Command.execute()` returned malformed response.
diff --git a/plugins/shell/src/commands.rs b/plugins/shell/src/commands.rs
index 77aee699..dce61ec5 100644
--- a/plugins/shell/src/commands.rs
+++ b/plugins/shell/src/commands.rs
@@ -170,6 +170,7 @@ fn prepare_cmd<R: Runtime>(
 }
 
 #[derive(Serialize)]
+#[serde(untagged)]
 enum Output {
     String(String),
     Raw(Vec<u8>),
@@ -179,9 +180,7 @@ enum Output {
 pub struct ChildProcessReturn {
     code: Option<i32>,
     signal: Option<i32>,
-    #[serde(flatten)]
     stdout: Output,
-    #[serde(flatten)]
     stderr: Output,
 }