New CLI bwrap sandbox fails before shell: RTM_NEWADDR loopback Operation not permitted

Resolved 💬 4 comments Opened Apr 23, 2026 by aiconvergence-collab Closed May 5, 2026

💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

What version of Codex CLI is running?

0.124

What subscription do you have?

Pro 5x

Which model were you using?

All

What platform is your computer?

Linux

What terminal emulator and version are you using (if applicable)?

None

What issue are you seeing?

Every exec command fails before bash starts:

bwrap: loopback: Failed RTM_NEWADDR: Operation not permitted

Expected:
Local commands should run, or sandbox should be disabled when full permissions
are granted.

Regression:
Reverting to Codex CLI 0.123 fixes it.

What steps can reproduce the bug?

Any attempt to access internal computer files.

What is the expected behavior?

Access

Additional information

Important. Regressing to 0.123 fixes the issue but doesn't allow the use of GPT 5.5

View original on GitHub ↗

4 Comments

github-actions[bot] contributor · 4 months ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

#17969
#19210
#17525
#18185

Powered by Codex Action

Your-Name-Here · 4 months ago

I wanted to add a note for people that find this in the future.

The note saying that regressing to 0.123.0 fixed this issue for the OP. I found that not to be true and found a fix and documented in my report https://github.com/openai/codex/issues/19285

As well as a possible stop-gap for maintainers.

cn3m0 · 4 months ago

I can confirm this regression on Linux as well.

This started after an update introduced about 1 hour ago.

Environment

codex-cli 0.124.0
Kernel:
Linux nautilus-yoga 6.14.0-1016-oem #16-Ubuntu SMP PREEMPT_DYNAMIC Tue Oct 21 09:55:24 UTC 2025 x86_64
Distro:
KDE neon User Edition 24.04 (noble)

Commands/output

$ codex --version
codex-cli 0.124.0

$ uname -a
Linux nautilus-yoga 6.14.0-1016-oem #16-Ubuntu SMP PREEMPT_DYNAMIC Tue Oct 21 09:55:24 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

$ lsb_release -a
No LSB modules are available.
Distributor ID: Neon
Description:    KDE neon User Edition
Release:        24.04
Codename:       noble

Symptom

All local exec commands fail before shell startup with:

bwrap: loopback: Failed RTM_NEWADDR: Operation not permitted

This blocks normal work in CLI sessions.

viyatb-oai contributor · 3 months ago

please follow the instructions on https://developers.openai.com/codex/concepts/sandboxing#prerequisites for ubuntu 24.04 and let me know if you can still reproduce this on latest codex release.