# Block Weakened Build Hardening

Block Weakened Build Hardening: what it does, its label on each agent, what it misses, and examples.

Catalog policy hardening-flags, version 0.1.2, labelled blocks on Claude Code.

> Ask the user before running any command on this page: each one changes how their agent or repository behaves.

## What it does

Blocks added settings that weaken compiler, linker, Rust or kernel hardening, in CMake, Make, meson, configure.ac, Cargo, build.rs, Go release scripts, Dockerfiles and kernel config: no stack protector, FORTIFY_SOURCE off, non-PIE, execstack, norelro, CET off, kernel KASLR/RWX off. Asks on Rust release overflow-checks off, /dev/mem. Not MSVC, sysctl or container settings; misses environment flags, generated files. Runs: commit, agent write, turn's end, CI. Waiver: 'pragma: allowlist hardening-flag'.

## On each agent

| Agent | Label | What it does there |
| --- | --- | --- |
| Claude Code | Blocks | Blocks on an agent's file writes and at turn end |
| Cursor | Blocks | Blocks on an agent's file writes and at turn end. Where its description says it asks, it refuses at both points, because this client cannot prompt at either point |
| Codex | Blocks | Blocks on an agent's file writes and at turn end. Where its description says it asks, it refuses at both points, because this client cannot prompt at either point. If the hook errors, the action goes through (not witnessed; the vendor's row is only partly live-run) |
| GitHub Copilot | Blocks | Blocks at turn end only. It does not check a file write when it happens. Where its description says it asks, it refuses at turn end, because this client cannot prompt there. If the hook errors, the action goes through (not witnessed; the vendor's row is only partly live-run) |
| Devin | Blocks | Blocks at turn end only. It does not check a file write when it happens. Where its description says it asks, it refuses at turn end, because this client cannot prompt there. If the hook errors, the action goes through (vendor docs only, not witnessed) |
| Grok | Not graded | Not graded yet for Grok |
| goose | Not graded | Not graded yet for goose |
| Antigravity | Not graded | Not graded yet for Antigravity |
| OpenHands | Not graded | Not graded yet for OpenHands |
| Kimi Code | Not graded | Not graded yet for Kimi Code |
| Factory Droid | Not graded | Not graded yet for Factory Droid |

## What it misses

This policy does not state what it misses.

## Examples from its eval suite

Refused: A CMake change adds -fno-stack-protector to target_compile_options.

Allowed: A change adds -fstack-protector-strong.

## More

- [The policy on the catalog pages](https://chock.sh/coding/policies/hardening-flags/)
- [Source at the pinned catalog commit](https://github.com/open-coder-ai/chock-catalog/tree/1e60d211c1bb767152c6ab0167932da06ab3a10f/base/hardening-flags)


---

Built from engine [5a4b6287a46e](https://github.com/open-coder-ai/chock/commit/5a4b6287a46e07f9f856d9bbe10622bd1ff2e021) and catalog [1e60d211c1bb](https://github.com/open-coder-ai/chock-catalog/commit/1e60d211c1bb767152c6ab0167932da06ab3a10f).