2026-03 Monthly Summary — OpenAI Codex (openai/codex) Overview: In March 2026, delivered security-focused network proxy hardening, reliable sandboxing, and robust workspace/config semantics across Linux, macOS, and Windows. These changes reduce surface area, improve reliability of local IPC, and strengthen trust resolution, enabling safer feature rollouts and smoother developer workflows.

February 2026: Security hardening, sandbox reliability, and network-policy governance delivered across the zed-industries/codex and openai/codex repositories. Key features include hardened Git command safety (preventing unsafe auto-approval of destructive commands), vendored Bubblewrap wired with FFI for linux-sandbox and corresponding build plumbing, and the introduction of codex-secrets for secure local secret storage. Structured policy signaling and network-approval plumbing were rolled out across core, network-proxy, and the UI, with an explicit emphasis on auditable decisions. Additional Linux sandbox hardening blocks io_uring syscalls in no-network mode. These efforts enhance security, reliability, and governance while enabling secure secret management and safer model-network interactions.

January 2026 performance summary for zed-industries/codex: Key features delivered: - Arg0 helper PATH security hardening: scoped wrapper binaries under CODEX_HOME, rejected unsafe CODEX_HOME configurations, and improved directory permissions to prevent PATH-based privilege risks. - Linux sandbox security hardening: added read-only mounts for sensitive dirs, corrected UID/GID mapping after unshare, introduced early PR_SET_NO_NEW_PRIVS with a Landlock fallback, and removed the pre-Landlock bind-mount step to simplify and strengthen containment. - Network proxy service with policy enforcement: created a local network proxy with policy evaluation and blocking callbacks; introduced a SOCKS5 proxy listener with policy enforcement and UDP support (initial SOCKS5 capability gated behind config). - CI and tooling upgrade: upgraded Rust toolchain to 1.92.0 across CI, implemented clippy-derived fixes (Default for enums), and tidied TUI/test configurations to improve build reliability. Major bugs fixed: - Harden arg0 PATH handling (#8766): ensured CODEX_HOME-based PATH entries and fast-fail on unsafe configurations. - Linux sandbox UID/GID mapping fix after unshare (#9234): preserved correct user namespace mappings to avoid privilege escalations. - Fallback to Landlock-only when user namespaces are unavailable (#9250): enables sandbox protections even when namespaces are blocked and ensures PR_SET_NO_NEW_PRIVS is applied early. - Revert pre-Landlock bind mounts apply (#9300): simplified sandbox flow to rely on Landlock for filesystem restrictions. Overall impact and accomplishments: - Strengthened security posture with end-to-end sandbox hardening and policy-driven network controls, reducing risk of data leakage and privilege escalation. - Improved reliability and maintainability through tooling upgrades, faster feedback loops, and clearer enforcement of security policies. Technologies/skills demonstrated: - Rust tooling and ecosystem (1.92.0), clippy, cargo test; Linux security primitives (namespaces, unshare, read-only mounts, Landlock, PR_SET_NO_NEW_PRIVS); network proxy design (HTTP/SOCKS5, policy evaluation); software architecture for policy-driven runtime security.