Docker Exit Code 126: Permission Problem Fix

Symptom

Container exits instantly with code 126.

The command inside the image exists but is not executable by that user.

1. Inspect the entrypoint bitdocker run --rm <image> ls -la /entrypoint.sh

2. Fix the exec bit at build timeRUN chmod +x /entrypoint.sh

3. Confirm the shebang is righthead -1 /entrypoint.sh # #!/bin/sh or #!/bin/bash

Set the exec bit in the Dockerfile, not in CI tricks.

Spinning up a fresh box to reproduce or escape this error?

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Last reviewed 2026-10-02 · NinjaOps SEO grid · DevOps blog