firewall-patterns SKILL.md skillA
firewall-patterns from hermeticormus/libresecops-claude-code is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add hermeticormus/libresecops-claude-code/firewall-patterns@git:20260930.71a2663Pins git:20260930.71a2663 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- hermeticormus/libresecops-claude-code
- Path
plugins/network-security/skills/firewall-patterns/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260930.71a2663, committed Sep 30, 2026
- First version recorded
- Feb 25, 2026
- Size
- 9,211 bytes
- Repository stars
- 4
- License
- MIT
Firewall design reference with iptables and nftables rulesets, cloud security group patterns, stateful versus stateless processing, and common rule mistakes. Use when writing or reviewing host or cloud firewall rules.
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
# Firewall Patterns > iptables/nftables rulesets, cloud security group patterns, and firewall design principles. ## Knowledge Base ### Firewall Processing Models Different firewalls process rules differently. Understanding the model is critical for correct configuration: | Firewall | Processing | Implication | |----------|-----------|-------------| | **iptables** | Sequential (first match wins) | Rule order matters. A broad ACCEPT before a specific DROP makes the DROP unreachable. | | **nftables** | Sequential within chains, but supports sets and maps for efficiency | More flexible than iptables, same sequential logic. | | **AWS Security Groups** | All rules evaluated, any allow = allow. No deny rules. | Cannot deny specific IPs. Denies require NACLs. Stateful. | | **AWS NACLs** | Sequential by rule number (lowest first). Has explicit deny. | Stateless -- must allow return traffic explicitly. | | **Azure NSGs** | Priority-based (lowest number = highest priority) | Has deny rules. Stateful. Default rules at priority 65000+. | | **GCP Firewall Rules** | Priority-based (lowest number = highest priority) | Has deny rules. Implied deny-all ingress, allow-all egress. | …
Read the whole file at its exact version.
How to install
mdr add hermeticormus/libresecops-claude-code/firewall-patterns@sha256:f6542e0b162b773bThe line at the top of this page pins the label git:20260930.71a2663, 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_bv36hds3t2bbxj6s)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Feb 25, 2026 and Sep 30, 2026, about one every 218 days. Its first recorded version is graded C and its latest A.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260930.71a2663 latest | 2026-09-30 | 71a2663 | 9,211 B | A | view · diff |
| git:20260225.4a0a620 | 2026-02-25 | 4a0a620 | 8,943 B | C | view |
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 (9211 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
hermeticormus/libresecops-claude-code · 4 stars · license MIT · pushed 2026-10-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_bv36hds3t2bbxj6s GET https://markdownregistry.com/api/v1/resolve?ref=hermeticormus/libresecops-claude-code/firewall-patterns GET https://markdownregistry.com/api/v1/blob/f6542e0b162b773b69e2f9179ccd6471aec017fa0505e20a2e3cbf4db821d69e
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.