diff --git a/codex-cli/src/components/chat/image-picker-overlay.tsx b/codex-cli/src/components/chat/image-picker-overlay.tsx
index c2431856cc..ea134e0a85 100644
--- a/codex-cli/src/components/chat/image-picker-overlay.tsx
+++ b/codex-cli/src/components/chat/image-picker-overlay.tsx
@@ -44,6 +44,19 @@ export default function ImagePickerOverlay({
   // Keep track of currently highlighted item so <Enter> can act synchronously.
   const highlighted = useRef<PickerItem | null>(items[0] ?? null);
 
+  // Ensure we only invoke `onPick` / `onCancel` / `onChangeDir` once for the
+  // life‑time of the overlay.  Depending on the environment a single <Enter>
+  // key‑press can bubble through *three* different handlers (raw `data` event,
+  // `useInput`, plus `SelectInput`\'s `onSelect`).  Without this guard the
+  // parent component would receive duplicate attachments.
+  const actedRef = useRef(false);
+
+  function perform(action: () => void) {
+    if (actedRef.current) return;
+    actedRef.current = true;
+    action();
+  }
+
   // DEBUG: log all raw data when DEBUG_OVERLAY enabled (useful for tests)
   const { stdin: inkStdin } = useStdin();
   React.useEffect(() => {
@@ -68,19 +81,21 @@ export default function ImagePickerOverlay({
         const item = highlighted.current;
         if (!item) return;
 
-        if (item.value === "__UP__") {
-          onChangeDir(path.dirname(cwd));
-        } else if (item.label.endsWith("/")) {
-          onChangeDir(item.value);
-        } else {
-          onPick(item.value);
-        }
+        perform(() => {
+          if (item.value === "__UP__") {
+            onChangeDir(path.dirname(cwd));
+          } else if (item.label.endsWith("/")) {
+            onChangeDir(item.value);
+          } else {
+            onPick(item.value);
+          }
+        });
         return;
       }
 
       // ESC (\u001B) or Backspace (\x7f)
       if (str === "\u001b" || str === "\x7f") {
-        onCancel();
+        perform(onCancel);
       }
     }
     if (inkStdin) inkStdin.on('data', onData);
@@ -99,9 +114,9 @@ export default function ImagePickerOverlay({
       // eslint-disable-next-line no-console
       console.log('[overlay] root useInput', JSON.stringify(input), key.return);
     }
-    if (key.escape || key.backspace || input === "\u007f") {
+      if (key.escape || key.backspace || input === "\u007f") {
       if (process.env.DEBUG_OVERLAY) console.log('[overlay] cancel');
-      onCancel();
+      perform(onCancel);
     } else if (key.return) {
       // Act on the currently highlighted item synchronously so tests that
       // simulate a bare "\r" keypress without triggering SelectInput’s
@@ -117,13 +132,15 @@ export default function ImagePickerOverlay({
         console.log('[overlay] return on', item.label, item.value);
       }
 
-      if (item.value === "__UP__") {
-        onChangeDir(path.dirname(cwd));
-      } else if (item.label.endsWith("/")) {
-        onChangeDir(item.value);
-      } else {
-        onPick(item.value);
-      }
+      perform(() => {
+        if (item.value === "__UP__") {
+          onChangeDir(path.dirname(cwd));
+        } else if (item.label.endsWith("/")) {
+          onChangeDir(item.value);
+        } else {
+          onPick(item.value);
+        }
+      });
     }
     },
     { isActive: true },
diff --git a/codex-cli/src/components/chat/terminal-chat-input.tsx b/codex-cli/src/components/chat/terminal-chat-input.tsx
index 92df2600b7..8c3c0ab0a9 100644
--- a/codex-cli/src/components/chat/terminal-chat-input.tsx
+++ b/codex-cli/src/components/chat/terminal-chat-input.tsx
@@ -468,8 +468,10 @@ export default function TerminalChatInput({
           // Remove trailing '@' sentinel from draft input
           setInput((prev) => (prev.endsWith("@") ? prev.slice(0, -1) : prev));
 
-          // Track attachment separately
-          setAttachedImages((prev) => [...prev, filePath]);
+          // Track attachment separately, but avoid duplicates
+          setAttachedImages((prev) =>
+            prev.includes(filePath) ? prev : [...prev, filePath],
+          );
 
           if (process.env.DEBUG_TCI) {
             // eslint-disable-next-line no-console
diff --git a/codex-cli/tests/attachment-preview.test.tsx b/codex-cli/tests/attachment-preview.test.tsx
index 99b3f90f39..7e414076d4 100644
--- a/codex-cli/tests/attachment-preview.test.tsx
+++ b/codex-cli/tests/attachment-preview.test.tsx
@@ -71,7 +71,8 @@ describe("Chat input attachment preview", () => {
     await type(stdin, "@", flush);
     await type(stdin, "\r", flush); // choose first
 
-    expect(lastFrameStripped()).toContain("foo.png");
+    const frame1 = lastFrameStripped();
+    expect(frame1.match(/foo\.png/g)?.length ?? 0).toBe(1);
 
     await type(stdin, "\x15", flush); // Ctrl+U
 
diff --git a/codex-cli/tests/backspace-delete-image.test.tsx b/codex-cli/tests/backspace-delete-image.test.tsx
index 752e93ee44..d9475631b6 100644
--- a/codex-cli/tests/backspace-delete-image.test.tsx
+++ b/codex-cli/tests/backspace-delete-image.test.tsx
@@ -69,8 +69,8 @@ describe("Backspace deletes attached image", () => {
     await type(stdin, "@", flush);
     console.log('AFTER @', lastFrameStripped());
     await type(stdin, "\r", flush);
-    console.log('FRAME1', lastFrameStripped());
-    expect(lastFrameStripped()).toContain("bar.png");
+    const frame1 = lastFrameStripped();
+    expect(frame1.match(/bar\.png/g)?.length ?? 0).toBe(1);
 
     await type(stdin, "\x7f", flush);