email-security SKILL.md skillA

email-security from coco-research/coco is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned

mdr add coco-research/coco/email-security@git:20260914.480426e

Pins git:20260914.480426e in mdr.lock. Pin the fingerprint instead.

Audit grade: A, 17 of 17 checks passed
Kind: SKILL.md skill
Repository: coco-research/coco
Path: systems/reverse-skill/skills/email-security/SKILL.md
Versions recorded: 1
Latest version: git:20260914.480426e, committed Sep 14, 2026
Size: 1,106 bytes
Repository stars: 827
License: a license file GitHub does not identify

Use for authorized email security review including phishing analysis, header authentication (SPF/DKIM/DMARC), BEC patterns, and mailbox token abuse research.

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

# Email Security & Phishing Analysis

## 适用场景

- 钓鱼邮件拆解与 IOC
- SPF/DKIM/DMARC 配置评估
- BEC 商务邮件欺诈模式
- OAuth 应用钓鱼 / 邮箱令牌滥用（联合 llm/cloud 身份）
- 安全意识演练设计（授权）

## 工作流

```text
□ 完整原始头：Received 链、From/Return-Path 一致性
□ SPF/DKIM/DMARC 对齐结果
□ URL 沙箱与附件静态（联合 malware-analysis）
□ 仿冒品牌与回复地址差异
□ 租户：反钓鱼策略、外部标记、MFA、OAuth app 同意
```

## 工具链

| 工具 | 用途 |
|------|------|
| 邮件客户端「查看源」 | 头 |
| dig/nslookup | SPF/DMARC 记录 |
| urlscan / 沙箱 | 链接与附件 |
| 租户管理中心 | 策略 |

## 参考

- `references/email-auth-checklist.md`
- `../malware-analysis/` `../attack-chain/`（钓鱼阶段） `../windows-ad/`（令牌）

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint

mdr add coco-research/coco/email-security@sha256:7717824a2d1946d9

The line at the top of this page pins the label git:20260914.480426e, 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.

Badge

[![mdr](https://markdownregistry.com/badge/art_qcqqhjtndn5s3lwm.svg)](https://markdownregistry.com/a/art_qcqqhjtndn5s3lwm)

2 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 1 version of this file, committed on Sep 14, 2026.

version	committed	commit	size	audit
git:20260914.480426e latest	2026-09-14	480426e	1,106 B	A	view

Audit of the latest version

A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.

pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (1106 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

GitHub

coco-research/coco · 827 stars · license a license file GitHub does not identify · pushed 2026-10-20 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_qcqqhjtndn5s3lwm
GET https://markdownregistry.com/api/v1/resolve?ref=coco-research/coco/email-security
GET https://markdownregistry.com/api/v1/blob/7717824a2d1946d9a08e623c0455130d0a9a3b50bca37495fe5acb9a93bc36a4

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.

More from coco-research/coco

AGENTS.md AGENTS.md file

coco-research/coco · AGENTS.md

git:20261007.61dca6d · audit A · 827 stars

create-rule SKILL.md skill

coco-research/coco · adapters/cursor/skills/create-rule/SKILL.md · Create Cursor rules for persistent AI guidance. Use when the user wants to create a rule, add coding standards, set up…