hunting-smart-contract-reentrancy SKILL.md skillA
hunting-smart-contract-reentrancy from unboundcompute/security-agent-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add unboundcompute/security-agent-skills/hunting-smart-contract-reentrancy@git:20260823.e797ed0Pins git:20260823.e797ed0 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- unboundcompute/security-agent-skills
- Path
skills/hunting-smart-contract-reentrancy/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260823.e797ed0, committed Aug 23, 2026
- Size
- 8,891 bytes
- Repository stars
- 26
- License
- MIT
Hunt a smart contract for state that is mutated after an external call, so an attacker re-enters before the update lands and acts on stale state. Covers a withdrawal or transfer that sends value before zeroing the balance, a call to an attacker-controlled contract or token that re-enters the same function, cross-function reentrancy where the callback re-enters a different function sharing the same state, a callback hook (a token receive hook, a fallback) that hands control to the attacker…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Hunting smart-contract reentrancy: acting on state that has not been updated yet Reentrancy is a control-flow bug: a contract makes an external call before it finishes updating its own state, and the callee, which the attacker controls, calls back in and finds the old state still in place. The classic shape is sending value before zeroing a balance, but it generalizes to any effect that lands after an interaction, across functions that share state and through callback hooks that hand the attacker control mid-update. This is a crowded topic, so the value is not naming the pattern but killing the lead that a guard or an already-updated state defeats. The dividing line from access control: if the fix is to reorder effects before interactions or add a mutex, it is reentrancy and belongs here; if the fix is to add or repair an authorization check, it belongs in the access-control skill. ## When to use - A function makes an external call (sends value, calls a token, invokes an attacker-supplyable address). - State that the function or a sibling depends on is updated after that external call. …
Read the whole file at its exact version.
How to install
mdr add unboundcompute/security-agent-skills/hunting-smart-contract-reentrancy@sha256:ee8098ec5953f45cThe line at the top of this page pins the label git:20260823.e797ed0, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_beykcdmiavhr2eb3)
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Versions
The registry has recorded 1 version of this file, committed on Aug 23, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (8891 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
unboundcompute/security-agent-skills · 26 stars · license MIT · pushed 2026-09-08 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_beykcdmiavhr2eb3 GET https://markdownregistry.com/api/v1/resolve?ref=unboundcompute/security-agent-skills/hunting-smart-contract-reentrancy GET https://markdownregistry.com/api/v1/blob/ee8098ec5953f45c0476694967a540448bf235f2fec4f8c45b7f7014a2ccba7a
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.