engage.cvediff

engage.cvediff is a command for Claude Code from hypnguyen1209/offensive-claude. It costs 19 tokens per session (467 once invoked), scanned A, original, MIT.

A command that finds the source-code commits that fixed a known security vulnerability, identified by its CVE number. A CVE is a public identifier for a specific software security flaw; the command can also compare the fix with the code before it.

In plain words
What is it for?
Use it to search OSV, NVD, and GitHub Advisories, select and verify a likely fix commit, and produce a gated code diff for further analysis.
Why use it?
Security advisories may point to several repositories or commits, making the official fix and its underlying cause difficult to confirm.

Command for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the offensive-claude plugin — 30 skills, 18 commands, 8 agents, 1 hook shipped together

Good fit Use it to search OSV, NVD, and GitHub Advisories, select and verify a likely fix commit, and produce a gated code diff for further analysis.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/hypnguyen1209/offensive-claude/engage.cvediff
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Clone the repo
git clone --depth 1 https://github.com/hypnguyen1209/offensive-claude

Made for: Claude Code.

Or install offensive-claude, the plugin that ships this one along with the rest of its 30 skills, 18 commands, 8 agents, 1 hook.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for engage.cvediff

README.md
[![agentmods](https://agentmods.dev/badge/commands/hypnguyen1209/offensive-claude/engage.cvediff/github.svg)](https://agentmods.dev/commands/hypnguyen1209/offensive-claude/engage.cvediff)
Your own site
<a href="https://agentmods.dev/commands/hypnguyen1209/offensive-claude/engage.cvediff"><img src="https://agentmods.dev/badge/commands/hypnguyen1209/offensive-claude/engage.cvediff/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for engage.cvediff

Your own site · 80×15
<a href="https://agentmods.dev/commands/hypnguyen1209/offensive-claude/engage.cvediff"><img src="https://agentmods.dev/badge/commands/hypnguyen1209/offensive-claude/engage.cvediff.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 19 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 467 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00019 $0.00467
Opus 5 $0.00010 $0.00234
Sonnet 5 $0.00004 $0.00093
Haiku 4.5 $0.00002 $0.00047

Measured 12d ago against content hash 39ccd1d59fd9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

engage.cvediff scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

commands/engage.cvediff.md · 33 lines

What it actually says

/engage.cvediff

Locates the fix commit(s) for a CVE across OSV / NVD / GitHub Advisories, de-duplicates them, and optionally clones (scope-gated, hardened) to emit git diff fix^..fix — the start of n-day patch diffing. Feeds skills/reverse-engineering/references/patch-diffing-protocol.md and can chain into /engage.crash for root-cause + exploitability.

Usage

/engage.cvediff <CVE-id> [--source osv,nvd,ghsa] [--diff --repo <url> --sha <fix>]

Process

  1. Discovercve_diff.py find <CVE> queries each source, extracts every commit reference (github/gitlab/cgit + OSV GIT-range fixed events), merges by (repo, sha). A source that errors is recorded, not fatal.
  2. Pick the canonical fix — prefer a commit confirmed by ≥2 sources (also_in); verify the SHA exists in the repo before trusting it.
  3. Diff (gated)cve_diff.py diff <CVE> --repo <url> --sha <fix> --scope .engage/scope/scope.json. The repo host is checked against scope_guard FIRST (out-of-scope ⇒ refused, exit 3); the clone runs through safe_subprocess.git_safe (no hooks/prompt/host-config/ext-transport/symlinks).
  4. Root cause — feed the diff into patch-diffing (BinDiff/ghidriff for binaries) or read it directly; optionally /engage.crash to prove reachability + empirical exploitability.

Notes

  • Read-only public advisory APIs; the clone is the only state-changing step and it is scope-gated.
  • A missing/own­ership-changed fix commit is common — corroborate across sources; a single source is often wrong or stale.
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 12d ago First seen · 33 lines · 19 tokens per session scan A 39ccd1d59fd9

Subscribe to this mod's changes

engage.cvediff is a command published in the GitHub repository hypnguyen1209/offensive-claude (360 stars, last pushed 26d ago), licensed MIT. It adds 19 tokens to every session and 467 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.