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Michael Bolin 648a420cbf
fix: enforce sandbox envelope for zsh fork execution (#12800)
## Why
Zsh fork execution was still able to bypass the `WorkspaceWrite` model
in edge cases because the fork path reconstructed command execution
without preserving sandbox wrappers, and command extraction only
accepted shell invocations in a narrow positional shape. This can allow
commands to run with broader filesystem access than expected, which
breaks the sandbox safety model.

## What changed
- Preserved the sandboxed `ExecRequest` produced by
`attempt.env_for(...)` when entering the zsh fork path in
[`unix_escalation.rs`](https://github.com/openai/codex/blob/main/codex-rs/core/src/tools/runtimes/shell/unix_escalation.rs).
- Updated `CoreShellCommandExecutor` to execute the sandboxed command
and working directory captured from `attempt.env_for(...)`, instead of
re-running a freshly reconstructed shell command.
- Made zsh-fork script extraction robust to wrapped invocations by
scanning command arguments for `-c`/`-lc` rather than only matching the
first positional form.
- Added unit tests in `unix_escalation.rs` to lock in wrapper-tolerant
parsing behavior and keep unsupported shell forms rejected.
- Tightened the regression in
[`skill_approval.rs`](https://github.com/openai/codex/blob/main/codex-rs/core/tests/suite/skill_approval.rs):
- `shell_zsh_fork_still_enforces_workspace_write_sandbox` now uses an
explicit `WorkspaceWrite` policy with `exclude_tmpdir_env_var: true` and
`exclude_slash_tmp: true`.
- The test attempts to write to `/tmp/...`, which is only reliably
outside writable roots with those explicit exclusions set.

## Verification
- Added and passed the new unit tests around `extract_shell_script`
parsing behavior with wrapped command shapes.
  - `extract_shell_script_supports_wrapped_command_prefixes`
  - `extract_shell_script_rejects_unsupported_shell_invocation`
- Verified the regression with the focused integration test:
`shell_zsh_fork_still_enforces_workspace_write_sandbox`.

## Manual Testing

Prior to this change, if I ran Codex via:

```
just codex --config zsh_path=/Users/mbolin/code/codex2/codex-rs/app-server/tests/suite/zsh --enable shell_zsh_fork
```

and asked:

```
what is the output of /bin/ps
```

it would run it, even though the default sandbox should prevent the
agent from running `/bin/ps` because it is setuid on MacOS.

But with this change, I now see the expected failure because it is
blocked by the sandbox:

```
/bin/ps exited with status 1 and produced no output in this environment.
```
2026-02-25 11:05:27 -08:00
.codex/skills Add PR babysitting skill for this repo (#12513) 2026-02-22 15:36:28 -08:00
.devcontainer chore: install an extension for TOML syntax highlighting in the devcontainer (#1650) 2025-07-22 10:58:09 -07:00
.github tests(js_repl): stabilize CI runtime test execution (#12407) 2026-02-24 21:04:34 -08:00
.vscode Move rust analyzer target dir (#5328) 2025-10-18 17:31:46 -07:00
codex-cli Update pnpm versions to fix cve-2026-24842 (#12009) 2026-02-19 14:27:55 -08:00
codex-rs fix: enforce sandbox envelope for zsh fork execution (#12800) 2026-02-25 11:05:27 -08:00
docs Agent jobs (spawn_agents_on_csv) + progress UI (#10935) 2026-02-24 21:00:19 +00:00
patches voice transcription (#3381) 2026-02-23 22:15:18 +00:00
scripts bazel: enforce MODULE.bazel.lock sync with Cargo.lock (#11790) 2026-02-14 02:11:19 +00:00
sdk/typescript Update pnpm versions to fix cve-2026-24842 (#12009) 2026-02-19 14:27:55 -08:00
shell-tool-mcp refactor: delete exec-server and move execve wrapper into shell-escalation (#12632) 2026-02-23 20:10:22 -08:00
third_party Add feature-gated freeform js_repl core runtime (#10674) 2026-02-11 12:05:02 -08:00
.bazelignore [bazel] Improve runfiles handling (#10098) 2026-01-29 00:15:44 +00:00
.bazelrc [bazel] Upgrade some rulesets in preparation for enabling windows (#11109) 2026-02-08 13:40:32 -08:00
.bazelversion [bazel] Upgrade to bazel9 (#9576) 2026-01-21 13:25:36 +00:00
.codespellignore feat(network-proxy): structured policy signaling and attempt correlation to core (#11662) 2026-02-13 09:01:11 +00:00
.codespellrc feat(network-proxy): structured policy signaling and attempt correlation to core (#11662) 2026-02-13 09:01:11 +00:00
.gitignore gitignore bazel-* (#8911) 2026-01-08 07:50:58 -08:00
.markdownlint-cli2.yaml fix(tui): document paste-burst state machine (#9020) 2026-01-13 11:48:31 -08:00
.npmrc chore: migrate to pnpm for improved monorepo management (#287) 2025-04-18 16:25:15 -07:00
.prettierignore [apply-patch] Clean up apply-patch tool definitions (#2539) 2025-08-21 20:07:41 -07:00
.prettierrc.toml Initial commit 2025-04-16 12:56:08 -04:00
AGENTS.md feat: discourage the use of the --all-features flag (#12429) 2026-02-20 23:02:24 -08:00
announcement_tip.toml nit: test an (#10892) 2026-02-06 14:41:53 +01:00
BUILD.bazel voice transcription (#3381) 2026-02-23 22:15:18 +00:00
CHANGELOG.md Documentation improvement: add missing period (#3754) 2025-10-30 13:01:33 -07:00
cliff.toml docs(changelog): update install command to @openai/codex@<version> (#2073) 2025-10-18 11:02:22 -07:00
defs.bzl [bazel] Fix proc_macro_dep libs (#12274) 2026-02-19 13:38:37 -08:00
flake.lock fix(nix): update flake for newer Rust toolchain requirements (#10302) 2026-01-31 11:34:53 -08:00
flake.nix fix(nix): use correct version from Cargo.toml in flake build (#11770) 2026-02-13 12:19:25 -08:00
justfile feat: discourage the use of the --all-features flag (#12429) 2026-02-20 23:02:24 -08:00
LICENSE Initial commit 2025-04-16 12:56:08 -04:00
MODULE.bazel voice transcription (#3381) 2026-02-23 22:15:18 +00:00
MODULE.bazel.lock Revert "fix(bazel): replace askama templates with include_str! in memories" (#12795) 2026-02-25 18:06:17 +00:00
NOTICE Add feature-gated freeform js_repl core runtime (#10674) 2026-02-11 12:05:02 -08:00
package.json Update pnpm versions to fix cve-2026-24842 (#12009) 2026-02-19 14:27:55 -08:00
pnpm-lock.yaml chore: ensure pnpm-workspace.yaml is up-to-date (#10140) 2026-01-29 10:49:03 -08:00
pnpm-workspace.yaml chore: ensure pnpm-workspace.yaml is up-to-date (#10140) 2026-01-29 10:49:03 -08:00
rbe.bzl feat: update Docker image digest to reflect #12205 (#12372) 2026-02-24 22:19:46 -08:00
README.md docs: mention Codex app in README intro (#11926) 2026-02-16 17:35:05 +01:00
SECURITY.md docs: add codex security policy (#12193) 2026-02-19 09:12:59 -08:00

npm i -g @openai/codex
or brew install --cask codex

Codex CLI is a coding agent from OpenAI that runs locally on your computer.

Codex CLI splash


If you want Codex in your code editor (VS Code, Cursor, Windsurf), install in your IDE.
If you want the desktop app experience, run codex app or visit the Codex App page.
If you are looking for the cloud-based agent from OpenAI, Codex Web, go to chatgpt.com/codex.


Quickstart

Installing and running Codex CLI

Install globally with your preferred package manager:

# Install using npm
npm install -g @openai/codex
# Install using Homebrew
brew install --cask codex

Then simply run codex to get started.

You can also go to the latest GitHub Release and download the appropriate binary for your platform.

Each GitHub Release contains many executables, but in practice, you likely want one of these:

  • macOS
    • Apple Silicon/arm64: codex-aarch64-apple-darwin.tar.gz
    • x86_64 (older Mac hardware): codex-x86_64-apple-darwin.tar.gz
  • Linux
    • x86_64: codex-x86_64-unknown-linux-musl.tar.gz
    • arm64: codex-aarch64-unknown-linux-musl.tar.gz

Each archive contains a single entry with the platform baked into the name (e.g., codex-x86_64-unknown-linux-musl), so you likely want to rename it to codex after extracting it.

Using Codex with your ChatGPT plan

Run codex and select Sign in with ChatGPT. We recommend signing into your ChatGPT account to use Codex as part of your Plus, Pro, Team, Edu, or Enterprise plan. Learn more about what's included in your ChatGPT plan.

You can also use Codex with an API key, but this requires additional setup.

Docs

This repository is licensed under the Apache-2.0 License.