code_mode_host app-server runs with umask 0077, silently creating 0600/0700 project files that break multi-user deployments

Start by locating the code_mode_host app-server startup path and inspect how its process umask is established on Linux. Reproduce the issue in a multi-user deployment, then verify that project files and directories created by the app-server have usable permissions rather than silently becoming 0600/0700.

What version of Codex CLI is running?

codex-cli 0.146.1

What subscription do you have?

Pro

Which model were you using?

Gpt-5.6-sol

What platform is your computer?

Linux

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

Ghostty

Codex doctor report

{
  "schemaVersion": 1,
  "generatedAt": "1786029303s since unix epoch",
  "overallStatus": "ok",
  "codexVersion": "0.146.1",
  "checks": {
    "app_server.status": {
      "id": "app_server.status",
      "category": "app-server",
      "status": "ok",
      "summary": "background server is running",
      "details": {
        "app-server version": "0.146.1",
        "control socket": "/root/.codex/app-server-control/app-server-control.sock",
        "daemon state dir": "/root/.codex/app-server-daemon",
        "mode": "ephemeral",
        "pid file": "/root/.codex/app-server-daemon/app-server.pid (missing)",
        "settings": "/root/.codex/app-server-daemon/settings.json (missing)",
        "status": "running",
        "update-loop pid file": "/root/.codex/app-server-daemon/app-server-updater.pid (missing)"
      },
      "remediation": null,
      "durationMs": 170
    },
    "auth.credentials": {
      "id": "auth.credentials",
      "category": "auth",
      "status": "ok",
      "summary": "auth is configured",
      "details": {
        "auth file": "/root/.codex/auth.json",
        "auth storage mode": "File",
        "stored API key": "false",
        "stored ChatGPT tokens": "true",
        "stored agent identity": "false",
        "stored auth mode": "chatgpt"
      },
      "remediation": null,
      "durationMs": 0
    },
    "config.load": {
      "id": "config.load",
      "category": "config",
      "status": "ok",
      "summary": "config loaded",
      "details": {
        "CODEX_HOME": "/root/.codex",
        "config.toml": "/root/.codex/config.toml",
        "config.toml parse": "ok",
        "cwd": "/root",
        "enabled feature flags": "shell_tool, unified_exec, shell_snapshot, terminal_resize_reflow, sqlite, hooks, enable_request_compression, multi_agent, apps, tool_search_always_defer_mcp_tools, tool_suggest, plugins, in_app_browser, in_app_updates, browser_use, browser_use_full_cdp_access, browser_use_external, computer_use, remote_plugin, plugin_sharing, image_generation, resize_all_images, item_ids, skill_mcp_dependency_install, skill_search, mentions_v2, steer, guardian_approval, goals, collaboration_modes, tool_call_mcp_elicitation, auth_elicitation, personality, fast_mode, tui_app_server, remote_compaction_v2, workspace_dependencies",
        "feature flag overrides": "code_mode_host=false",
        "feature flags enabled": "37",
        "log dir": "/root/.codex/log",
        "mcp servers": "3",
        "model": "gpt-5.6-sol",
        "model provider": "openai",
        "sqlite home": "/root/.codex"
      },
      "remediation": null,
      "durationMs": 0
    },
    "git.environment": {
      "id": "git.environment",
      "category": "git",
      "status": "ok",
      "summary": "git version 2.34.1",
      "details": {
        ".git entry": "directory",
        "PATH git #1": "/usr/bin/git",
        "PATH git #2": "/bin/git",
        "PATH git entries": "2",
        "git build options": "git version 2.34.1; cpu: x86_64; no commit associated with this build; sizeof-long: 8; sizeof-size_t: 8; shell-path: /bin/sh",
        "git exec path": "/usr/lib/git-core",
        "git version": "git version 2.34.1",
        "repo detected": "true",
        "repo root": "/root",
        "selected git": "/usr/bin/git"
      },
      "remediation": null,
      "durationMs": 86
    },
    "installation": {
      "id": "installation",
      "category": "install",
      "status": "ok",
      "summary": "installation looks consistent",
      "details": {
        "PATH codex #1": "/root/.local/bin/codex",
        "current executable": "/root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/bin/codex",
        "install context": "npm (package /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl, bin /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/bin, resources /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/codex-resources, path /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/codex-path)",
        "managed by bun": "false",
        "managed by npm": "true",
        "managed by pnpm": "false",
        "managed package root": "/root/.local/lib/node_modules/@openai/codex",
        "npm update target": "/root/.local/lib/node_modules/@openai/codex"
      },
      "remediation": null,
      "durationMs": 76
    },
    "mcp.config": {
      "id": "mcp.config",
      "category": "mcp",
      "status": "ok",
      "summary": "MCP configuration is locally consistent",
      "details": {
        "configured servers": "3",
        "disabled servers": "0",
        "streamable_http servers": "3"
      },
      "remediation": null,
      "durationMs": 1007
    },
    "network.env": {
      "id": "network.env",
      "category": "network",
      "status": "ok",
      "summary": "network-related environment looks readable",
      "details": {
        "proxy env vars": "none"
      },
      "remediation": null,
      "durationMs": 0
    },
    "network.provider_reachability": {
      "id": "network.provider_reachability",
      "category": "reachability",
      "status": "ok",
      "summary": "active provider endpoints are reachable over HTTP",
      "details": {
        "ChatGPT base URL": "https://chatgpt.com/backend-api/ reachable (HTTP 403)",
        "reachability mode": "ChatGPT auth"
      },
      "remediation": null,
      "durationMs": 118
    },
    "network.websocket_reachability": {
      "id": "network.websocket_reachability",
      "category": "websocket",
      "status": "ok",
      "summary": "Responses WebSocket handshake succeeded",
      "details": {
        "DNS": "2 IPv4, 2 IPv6, first IPv6",
        "auth mode": "chatgpt",
        "connect timeout": "15000 ms",
        "endpoint": "wss://chatgpt.com/backend-api/<redacted>",
        "handshake result": "HTTP 101 Switching Protocols",
        "model provider": "openai",
        "models etag present": "true",
        "provider name": "OpenAI",
        "proxy env vars": "none",
        "reasoning header": "false",
        "server model present": "false",
        "supports websockets": "true",
        "wire API": "responses"
      },
      "remediation": null,
      "durationMs": 616
    },
    "runtime.provenance": {
      "id": "runtime.provenance",
      "category": "runtime",
      "status": "ok",
      "summary": "running npm on linux-x86_64",
      "details": {
        "commit": "unknown",
        "current executable": "/root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/bin/codex",
        "install method": "npm (package /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl, bin /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/bin, resources /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/codex-resources, path /root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/codex-path)",
        "platform": "linux-x86_64",
        "version": "0.146.1"
      },
      "remediation": null,
      "durationMs": 0
    },
    "runtime.search": {
      "id": "runtime.search",
      "category": "search",
      "status": "ok",
      "summary": "search is OK (bundled)",
      "details": {
        "search command": "/root/.local/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/codex-path/rg",
        "search command readiness": "file exists",
        "search provider": "bundled"
      },
      "remediation": null,
      "durationMs": 0
    },
    "sandbox.helpers": {
      "id": "sandbox.helpers",
      "category": "sandbox",
      "status": "ok",
      "summary": "sandbox configuration is readable",
      "details": {
        "approval policy": "OnRequest",
        "codex-linux-sandbox helper": "/root/.codex/tmp/arg0/codex-arg0ElRtnQ/codex-linux-sandbox",
        "execve wrapper helper": "/root/.codex/tmp/arg0/codex-arg0ElRtnQ/codex-execve-wrapper",
        "filesystem sandbox": "restricted",
        "network sandbox": "restricted"
      },
      "remediation": null,
      "durationMs": 0
    },
    "state.paths": {
      "id": "state.paths",
      "category": "state",
      "status": "ok",
      "summary": "state paths and databases are inspectable",
      "details": {
        "CODEX_HOME": "/root/.codex (dir)",
        "active rollout files": "614 files, 5738055544 total bytes, 9345367 average bytes",
        "archived rollout files": "13 files, 6031721 total bytes, 463978 average bytes",
        "goals DB": "/root/.codex/goals_1.sqlite (file)",
        "goals DB integrity": "ok",
        "log DB": "/root/.codex/logs_2.sqlite (file)",
        "log DB integrity": "ok",
        "log dir": "/root/.codex/log (dir)",
        "memories DB": "/root/.codex/memories_1.sqlite (file)",
        "memories DB integrity": "ok",
        "sqlite home": "/root/.codex (dir)",
        "state DB": "/root/.codex/state_5.sqlite (file)",
        "state DB integrity": "ok",
        "thread history DB": "/root/.codex/thread_history_1.sqlite (missing)",
        "thread history DB integrity": "skipped (missing)"
      },
      "remediation": null,
      "durationMs": 3608
    },
    "state.rollout_db_parity": {
      "id": "state.rollout_db_parity",
      "category": "threads",
      "status": "ok",
      "summary": "rollout files and state DB thread inventory agree",
      "details": {
        "default model provider": "openai",
        "rollout DB active files": "614",
        "rollout DB active rows": "614",
        "rollout DB archive mismatches": "0",
        "rollout DB archived files": "13",
        "rollout DB archived rows": "13",
        "rollout DB duplicate DB paths": "0",
        "rollout DB duplicate rollout thread ids": "0",
        "rollout DB malformed file names": "0",
        "rollout DB missing active rows": "0",
        "rollout DB missing archived rows": "0",
        "rollout DB model providers": "openai=627",
        "rollout DB rows": "627",
        "rollout DB scan cap reached": "false",
        "rollout DB scan errors": "0",
        "rollout DB sources": "subagent:other=384, vscode=112, exec=105, cli=18, subagent:thread_spawn=8",
        "rollout DB stale rows": "0"
      },
      "remediation": null,
      "durationMs": 463
    },
    "system.environment": {
      "id": "system.environment",
      "category": "system",
      "status": "ok",
      "summary": "OS language en-US",
      "details": {
        "EDITOR": "not set",
        "LANG": "en_US.UTF-8",
        "VISUAL": "not set",
        "os": "Ubuntu 22.4.0 (jammy) [64-bit]",
        "os language": "en-US",
        "os type": "Ubuntu",
        "os version": "22.4.0"
      },
      "remediation": null,
      "durationMs": 59
    },
    "terminal.env": {
      "id": "terminal.env",
      "category": "terminal",
      "status": "ok",
      "summary": "terminal metadata was detected",
      "details": {
        "SSH_CLIENT": "present",
        "SSH_CONNECTION": "present",
        "SSH_TTY": "present",
        "TERM": "xterm-ghostty",
        "color output": "enabled",
        "effective locale": "en_US.UTF-8",
        "stderr is terminal": "true",
        "stdin is terminal": "true",
        "stdout is terminal": "true",
        "terminal": "unknown",
        "terminal size": "160x57"
      },
      "remediation": null,
      "durationMs": 0
    },
    "terminal.title": {
      "id": "terminal.title",
      "category": "title",
      "status": "ok",
      "summary": "terminal title default",
      "details": {
        "terminal title activity": "true",
        "terminal title items": "activity, project-name",
        "terminal title project source": "git repo root",
        "terminal title project value": "root",
        "terminal title source": "default"
      },
      "remediation": null,
      "durationMs": 0
    },
    "updates.status": {
      "id": "updates.status",
      "category": "updates",
      "status": "ok",
      "summary": "update configuration is locally consistent",
      "details": {
        "cached latest version": "0.146.1",
        "check for update on startup": "true",
        "last checked at": "2026-08-05T23:31:45.463282819Z",
        "latest version": "0.146.1",
        "latest version status": "current version is not older",
        "npm update target": "/root/.local/lib/node_modules/@openai/codex",
        "update action": "npm install -g @openai/codex",
        "version cache": "/root/.codex/version.json"
      },
      "remediation": null,
      "durationMs": 172
    }
  }
}

What issue are you seeing?

The app-server that the Codex client launches with -c features.code_mode_host=true
runs with umask 0077, and every process it spawns inherits it — the code-mode
child, the sandbox launcher, bwrap, and every command a conversation executes. All
files created through code-mode conversations arrive 0600 and directories
0700 instead of the customary 0644/0755.

Verified via /proc/<pid>/status on the same machine, same version:

The vendored Bubblewrap deliberately saves and restores the parent's umask
(old_umask = umask (0); ... umask (old_umask); in vendor/bubblewrap/bubblewrap.c),
so the sandbox faithfully propagates the app-server's 0077 into user commands.

If the 0077 is intentional hardening for Codex-internal files, it leaks beyond
them: ordinary project files and production build artifacts (e.g. a Vite build)
come out owner-only with no warning. Git doesn't track 0600 vs 0644, and
single-user setups never notice. In our environment (Codex as root; nginx and
systemd services as non-root users; mode-preserving rsync -a deploys) this
caused public 403s on a deployed frontend and a PermissionError on a service
importing a newly created Python module. It took days to trace, because plain-CLI
sessions on the same box produced normal 0644 files the whole time, making the
failures look intermittent.

Also: codex features disable code_mode_host writes the config correctly
(codex features list shows false), but the client launcher's
-c features.code_mode_host=true command-line flag overrides it, so there is no
user-accessible way to opt out.

What steps can reproduce the bug?

1. Connect with a client that launches the code-mode app-server (process cmdline:
   codex -c features.code_mode_host=true app-server --listen).

2. In a conversation, run:

   umask; mkdir d; touch d/f; ls -la d

3. Observe:

   0077
   drwx------ d
   -rw------- d/f

4. Compare with a plain codex CLI session on the same machine:

   0022
   drwxr-xr-x
   -rw-r--r--

5. Confirm the host-side chain: grep Umask /proc/<app-server-pid>/status and
   each descendant — all 0077.

What is the expected behavior?

Files created by a user's commands in code-mode conversations should have the
same modes as in any other Codex session: 0644 files, 0755 directories (umask
0022). Specifically, one of:

• scope any 0077 hardening to Codex-internal files and run project-file
  operations at 0022, or
• make the umask configurable and/or honor codex features disable code_mode_host instead of overriding it with the launcher flag, or
• at minimum, document prominently that code-mode output is owner-only and must
  be permission-normalized before deployment.

Additional information

No response