diff --git a/.changes/updater-signer-files-without-extension.md b/.changes/updater-signer-files-without-extension.md
new file mode 100644
index 000000000..1ff41edbd
--- /dev/null
+++ b/.changes/updater-signer-files-without-extension.md
@@ -0,0 +1,6 @@
+---
+tauri-cli: patch:bug
+"@tauri-apps/cli": patch:bug
+---
+
+`tauri signer sign` doesn't work for files without an extension
diff --git a/crates/tauri-cli/src/helpers/updater_signature.rs b/crates/tauri-cli/src/helpers/updater_signature.rs
index 9367e7bad..ba9012359 100644
--- a/crates/tauri-cli/src/helpers/updater_signature.rs
+++ b/crates/tauri-cli/src/helpers/updater_signature.rs
@@ -120,9 +120,14 @@ where
 {
   let bin_path = bin_path.as_ref();
   // We need to append .sig at the end it's where the signature will be stored
-  let mut extension = bin_path.extension().unwrap().to_os_string();
-  extension.push(".sig");
-  let signature_path = bin_path.with_extension(extension);
+  // TODO: use with_added_extension when we bump MSRV to > 1.91'
+  let signature_path = if let Some(ext) = bin_path.extension() {
+    let mut extension = ext.to_os_string();
+    extension.push(".sig");
+    bin_path.with_extension(extension)
+  } else {
+    bin_path.with_extension("sig")
+  };
 
   let trusted_comment = format!(
     "timestamp:{}\tfile:{}",