extracting-nday-from-a-patch SKILL.md skillA
extracting-nday-from-a-patch 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/extracting-nday-from-a-patch@git:20260816.c75b58dPins git:20260816.c75b58d 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/extracting-nday-from-a-patch/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260816.c75b58d, committed Aug 16, 2026
- Size
- 6,434 bytes
- Repository stars
- 26
- License
- MIT
Turn a security patch or version diff into fresh findings: infer the fixed vulnerability from what the fix changed, reconstruct the pre-patch bug, then hunt the paths the fix did not cover and the same bug in code it never touched. Use when you have a fix commit, a vague advisory with a linked diff, a version bump, or a "security release" and want to know what it silently fixed and what it missed. Covers reading a fix as a treasure map, incomplete-fix analysis, and variant discovery in the…
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
# Extracting n-day from a patch: the fix is the map A security fix is a confession. It tells you exactly where the bug was, what the missing check should have been, and, by omission, which other paths the author did not think to cover. Reading a patch backward, from fix to bug, is one of the highest-yield techniques in vulnerability research: the hard part (locating the defect) is already done for you, and the incomplete fixes are waiting. ## When to use - A fix commit or security release landed and you want to know what it addressed. - An advisory is deliberately vague but links a diff, a PR, or a tag. - You maintain or depend on a fork and need to know if a fix upstream applies. - You confirmed one bug via its patch and want the instances the patch missed. ## Scope check You may read and reason about public patches and advisories freely. You may only *test or exploit* against code and systems you are authorized for (your own, OSS you run, CTF, in-scope engagement). Analysis is not authorization to attack. ## The loop 1. **Read the fix, infer the bug.** Look at what the patch *adds* or *tightens*, …
Read the whole file at its exact version.
How to install
mdr add unboundcompute/security-agent-skills/extracting-nday-from-a-patch@sha256:ffc00edbdf4cdb22The line at the top of this page pins the label git:20260816.c75b58d, 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_qgdo5sto3amfjgij)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Aug 16, 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 (6434 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_qgdo5sto3amfjgij GET https://markdownregistry.com/api/v1/resolve?ref=unboundcompute/security-agent-skills/extracting-nday-from-a-patch GET https://markdownregistry.com/api/v1/blob/ffc00edbdf4cdb22a332919eebb415c8486f07d04281709a0d2f3f4aa8323d9b
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.