Server actions fail to return specific binary files: ‘Cannot perform Construct on a detached ArrayBuffer’ error

[niels-bosman]

Link to the code that reproduces this issue

https://github.com/niels-bosman/next-server-action-binary-bug-reproduction

To Reproduce

1. Clone this repository: https://github.com/niels-bosman/next-server-action-binary-bug-reproduction
2. Run bun install
3. Go to /
4. Refresh and see the dev server crash

Current vs. Expected behavior

When returning binary data from a server action (either by reading a file via fs or fetching binary data from a Prisma database row), the response consistently fails for certain files. The underlying cause within those specific binary files is unclear.

In a minimal reproduction case, the issue occurs when reading a particular file from the filesystem and returning its bytes to the client. Other files work as expected, so the problem seems related to some property of the binary data itself.

Expected behavior:

The server action should successfully return all binary files as byte data without error.

Actual behavior:

For specific binary files, the request fails consistently with the following error in the server logs:

GET / 200 in 63ms
 ⨯ [Error: failed to pipe response] {
  [cause]: [Error: failed to write chunk to response] {
    [cause]: TypeError: Cannot perform Construct on a detached ArrayBuffer
        at new Uint8Array (<anonymous>)
  }
}
 ⨯ [Error: failed to pipe response] {
  page: '/',
  [cause]: [Error: failed to write chunk to response] {
    [cause]: TypeError: Cannot perform Construct on a detached ArrayBuffer
        at new Uint8Array (<anonymous>)
  }
}
TypeError: Cannot perform Construct on a detached ArrayBuffer
    at new Uint8Array (<anonymous>)

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 25.0.0: Mon Aug 25 21:17:56 PDT 2025; root:xnu-12377.1.9~3/RELEASE_ARM64_T6030
  Available memory (MB): 18432
  Available CPU cores: 12
Binaries:
  Node: 20.11.0
  npm: 10.5.0
  Yarn: 1.22.21
  pnpm: 8.15.4
Relevant Packages:
  next: 15.5.5 // Latest available version is detected (15.5.5).
  eslint-config-next: N/A
  react: 19.1.0
  react-dom: 19.1.0
  typescript: 5.9.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Server Actions, Turbopack

Which stage(s) are affected? (Select all that apply)

next dev (local), next start (local), Vercel (Deployed)

Additional context

The file is a gzipped version of the JSON file also included In the repository.

The error sometimes happens on Vercel with these error logs:

node:buffer:634
write: (buf, string, offset, len) => buf.utf8Write(string, offset, len),
^
RangeError: "offset" is outside of buffer bounds
at Object.write (node:buffer:634:46)
at fromStringFast (node:buffer:463:22)
at fromString (node:buffer:487:51)
at Function.from (node:buffer:297:12)
at console.<anonymous> (/opt/rust/nodejs.js:6:121)
at process.<anonymous> (/var/task/node_modules/next/dist/compiled/next-server/server.runtime.prod.js:14:40750)
at process.emit (node:events:536:35)
at process._fatalException (node:internal/process/execution:188:25) {
code: 'ERR_BUFFER_OUT_OF_BOUNDS'
}
Node.js v20.19.4

[niels-bosman]

@sebmarkbage @unstubbable Can we re-open this please. I installed the new canary versions and the issue persist in my reproduction repository.

❯ bun i && bun dev
bun install v1.2.23 (cf136713)

+ react@19.3.0-canary-58bdc0bb-20251019
+ react-dom@19.3.0-canary-58bdc0bb-20251019

3 packages installed [11.00ms]
$ next dev --turbopack
   ▲ Next.js 15.5.5 (Turbopack)
   - Local:        http://localhost:3000
   - Network:      http://192.168.1.180:3000

 ✓ Starting...
 ✓ Ready in 609ms
 ○ Compiling / ...
 ✓ Compiled / in 1141ms
 ⨯ [Error: aborted] { code: 'ECONNRESET', digest: '3862855039' }
 GET / 200 in 863ms
 ⨯ [Error: failed to pipe response] {
  [cause]: [Error: failed to write chunk to response] {
    [cause]: TypeError: Cannot perform Construct on a detached ArrayBuffer
        at new Uint8Array (<anonymous>)
  }
}
 ⨯ [Error: failed to pipe response] {
  page: '/',
  [cause]: [Error: failed to write chunk to response] {
    [cause]: TypeError: Cannot perform Construct on a detached ArrayBuffer
        at new Uint8Array (<anonymous>)
  }
}
TypeError: Cannot perform Construct on a detached ArrayBuffer
    at new Uint8Array (<anonymous>)
****

[unstubbable]

@niels-bosman Next.js is vendoring React for App Router. Installing a different version won't work. You need to wait for v16.0.0-canary.16 to be released which will include the React version with the fix.

[niels-bosman]

@unstubbable Is there any chance Next 15 can get some package updates in as well? We would rather not use a canary version on our production application if possible.

[github-actions]

This closed issue has been automatically locked because it had no new activity for 2 weeks. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.