Individual skill
email-header-injection
Email header injection and spoofing playbook. Use when testing contact forms, email APIs, password reset flows, or any feature that constructs SMTP messages with user-controlled fields. Covers CRLF injection in headers, SPF/DKIM/DMARC bypass, and phishing amplification.
skills/email-header-injection/SKILL.md
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- Last checked
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- Apache-2.0
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# SKILL: Email Header Injection — Expert Attack Playbook
> **AI LOAD INSTRUCTION**: Expert email header injection and authentication bypass. Covers SMTP CRLF injection, SPF/DKIM/DMARC circumvention, display name spoofing, and mail client rendering abuse. Base models miss the nuance between header injection (technical) and email auth bypass (protocol-level) — this skill covers both attack surfaces.
## 0. RELATED ROUTING
- [crlf-injection](../crlf-injection/SKILL.md) — general CRLF injection; email headers are a specific high-value sink
- [ssrf-server-side-request-forgery](../ssrf-server-side-request-forgery/SKILL.md) — when SMTP server is reachable via SSRF (gopher://smtp)
- [open-redirect](../open-redirect/SKILL.md) — redirect in password-reset emails as phishing amplification
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## 1. SMTP HEADER INJECTION FUNDAMENTALS
