How do I install the Ipxe Security Review skill?

Run npx skillmds@latest add ipxe/ipxe-security-review in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Ipxe Security Review safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Ipxe Security Review?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Ipxe Security Review free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Ipxe Security Review?

ipxe (@ipxe) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Ipxe Security Review by ipxe — Agent Skill

Name: Ipxe Security Review
Author: ipxe

Ipxe Security Review

Systematic memory-safety review of iPXE's attacker-facing parsers. Use when asked to hunt for vulnerabilities, audit a network-input parser, or review a FILE_SECBOOT(PERMITTED) file that handles DHCP / DNS / TFTP / HTTP / TLS / EAP / PeerDist data or downloaded images, for length, overflow, or underflow defects.

ipxe e680e45 2.5 KB Updated Sep 17, 2026

File contents

iPXE security review

The working conventions — threat model, scope, reporting format, and the codebase bounds contracts — are in AGENTS.md. Read them first. This skill is the step-by-step sweep procedure that applies them.

The sweep loop

Work one file at a time. Stop as soon as you find a confirmed defect.

Pick a target. A FILE_SECBOOT ( PERMITTED ) file that parses an attacker input (threat model in AGENTS.md). Prefer wire parsers with manual length / offset arithmetic.
Find the entry point — the *_rx / deliver / parse function where attacker bytes first arrive together with a length.
Establish reachability — confirm the value is attacker-controlled and the path is reachable from network input, not reached only through trusted input (operator-configured settings or the embedded/boot script).
Trace the arithmetic. Follow every length, offset, and count from the wire to its use. Flag:
- size_t underflow — a - b where a < b yields ~`SIZE_MAX` (reversed operands, or a missing header / trailer term).
- integer truncation — a length held in int / unsigned int then used as size_t (LP64: 64-bit size_t, 32-bit int).
- unchecked iob_pull / iob_unput (no bounds check — see include/ipxe/iobuf.h).
Verify against the real allocation. Use the documented helper contracts (AGENTS.md → Codebase contracts). Account for iobuf head / tailroom and the guaranteed end-of-image NUL.
Classify. An actual reachable defect → report. A provably in-bounds boundary case → note privately and move on. Do not emit theoretical findings.
Report, then stop.

Reporting

! path/file.c:NNN  <attacker input> → <bug class>

Follow with a few sentences: how it is reached, and the consequence. Nothing more. Stop so the maintainer can patch — do not batch defects and do not open PRs. Keep findings private until fixed.

Do not flag (see `AGENTS.md` → Patterns not to misread)

Composable-cleanup unreachable cleanup; count-then-clamp logical lengths; end-of-image NUL reads; compiler-elided VLAs.

---name: ipxe-security-reviewdescription: Systematic memory-safety review of iPXE's attacker-facing parsers. Use when asked to hunt for vulnerabilities, audit a network-input parser, or review a FILE_SECBOOT(PERMITTED) file that handles DHCP / DNS / TFTP / HTTP / TLS / EAP / PeerDist data or downloaded images, for length, overflow, or underflow defects.---# iPXE security reviewThe working conventions — threat model, scope, reporting format, and thecodebase bounds contracts — are in [`AGENTS.md`](../../../AGENTS.md). Readthem first. This skill is the step-by-step sweep procedure that appliesthem.## The sweep loopWork one file at a time. Stop as soon as you find a confirmed defect.1. **Pick a target.** A `FILE_SECBOOT ( PERMITTED )` file that parses an attacker input (threat model in `AGENTS.md`). Prefer wire parsers with manual length / offset arithmetic.2. **Find the entry point** — the `*_rx` / deliver / parse function where attacker bytes first arrive together with a length.3. **Establish reachability** — confirm the value is attacker-controlled and the path is reachable from network input, not reached only through trusted input (operator-configured settings or the embedded/boot script).4. **Trace the arithmetic.** Follow every length, offset, and count from the wire to its use. Flag: - `size_t` underflow — `a - b` where `a < b` yields ~`SIZE_MAX` (reversed operands, or a missing header / trailer term). - integer truncation — a length held in `int` / `unsigned int` then used as `size_t` (LP64: 64-bit `size_t`, 32-bit `int`). - unchecked `iob_pull` / `iob_unput` (no bounds check — see `include/ipxe/iobuf.h`).5. **Verify against the real allocation.** Use the documented helper contracts (`AGENTS.md` → Codebase contracts). Account for iobuf head / tailroom and the guaranteed end-of-image NUL.6. **Classify.** An actual reachable defect → report. A provably in-bounds boundary case → note privately and move on. Do not emit theoretical findings.7. **Report, then stop.**## Reporting ! path/file.c:NNN <attacker input> → <bug class>Follow with a few sentences: how it is reached, and the consequence.Nothing more. Stop so the maintainer can patch — do not batch defects anddo not open PRs. Keep findings private until fixed.## Do not flag (see `AGENTS.md` → Patterns not to misread)Composable-cleanup unreachable cleanup; count-then-clamp logical lengths;end-of-image NUL reads; compiler-elided VLAs.

Frequently asked questions