New: 98,000+ skills indexed from GitHub repos with 100+ stars · every skill safety-checkedBrowse top skillsTop skills
Esc to closeBrowse all skills
Submit a skillBrowse skills
Submit a skillBrowse skills

Agent skill

Analyzing Tls Certificate Transparency Logs

by mukul975 in mukul975/Anthropic-Cybersecurity-Skills

Queries Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT.

Apache-2.0Auto-check passedSecurity

Install Analyzing Tls Certificate Transparency Logs

skills CLI
$ npx skills add mukul975/Anthropic-Cybersecurity-Skills --skill analyzing-tls-certificate-transparency-logs -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install mukul975/Anthropic-Cybersecurity-Skills analyzing-tls-certificate-transparency-logs --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/mukul975/Anthropic-Cybersecurity-Skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/analyzing-tls-certificate-transparency-logs .claude/skills/analyzing-tls-certificate-transparency-logs && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
analyzing-tls-certificate-transparency-logs
GitHub stars
34k
Token cost
~745 tokens
SKILL.md length
141 words
Files
4 (incl. scripts, references)
Skills in repo
644
Repo updated
First seen
Licence
Apache-2.0

At a glance

Queries Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT.

  • Works in 5 steps: Query crt.sh for all certificates… → Identify certificates with typosquatting… → Flag certificates from unexpected CAs → …
  • Proactive phishing domain detection and certificate monitoring
  • SKILL.md covers When to Use, Prerequisites, Instructions and Examples
  • Runs Python scripts from its folder

What it does

Analyzing Tls Certificate Transparency Logs is an agent skill from mukul975/Anthropic-Cybersecurity-Skills. Queries Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT. Monitors newly issued certificates for typosquatting and brand impersonation using Levenshtein distance. Use for proactive phishing domain detection and certificate monitoring.

Its SKILL.md is about 750 tokens, which your agent loads only when the skill is triggered. The skill folder holds 5 other files, including scripts and reference files (for example `references/api-reference.md` and `scripts/agent.py`).

It sits in Security, covering Cloud networking and Supply chain security. The repository describes itself as: 817 structured cybersecurity skills for AI agents · Mapped to 6 frameworks: MITRE ATT&CK, NIST CSF 2.0, MITRE ATLAS, D3FEND, NIST AI RMF & MITRE F3 (Fight Fraud) · agentskills.io…. The licence is Apache-2.0.

When your agent uses it

  • Proactive phishing domain detection and certificate monitoring
  • Tasks that involve Cloud networking
  • Tasks that involve Supply chain security

Example prompts

  • “Use the analyzing-tls-certificate-transparency-logs skill to query Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains…”
  • “/analyzing-tls-certificate-transparency-logs”

Requirements

  • Python 3

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

  1. Query crt.sh for all certificates matching your domain pattern
  2. Identify certificates with typosquatting variations (Levenshtein distance)
  3. Flag certificates from unexpected CAs
  4. Monitor for wildcard certificates on suspicious subdomains
  5. Cross-reference with known phishing infrastructure

What it can do on your machine

Read from SKILL.md and the folder at commit 54a7988. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    Ships 1 file in scripts/ (Python), which the agent can run.

    From the folder's file list and the shell code blocks in SKILL.md.

  • Network

    No URLs in SKILL.md.

    From URLs in SKILL.md, links to its own repository left out.

  • Credentials

    Names no API keys, tokens, secrets or passwords.

    From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Analyzing Tls Certificate Transparency Logs loads about 745 tokens when it runs, and up to ~1.1k if it reads all its reference files. Until then it costs about 90 tokens; SKILL.md has 141 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~90
When it runs · the whole SKILL.md, loaded when a task matches
~745
With references · SKILL.md plus every file in references/, read only if the agent opens them
~1.1k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.

SKILL.md

The full file from mukul975/Anthropic-Cybersecurity-Skills at commit 54a7988, republished under its Apache-2.0 licence (© mukul975). 141 words, ~745 tokens.

Download SKILL.mdSave it as .claude/skills/analyzing-tls-certificate-transparency-logs/SKILL.md (or your agent's skills folder). This skill also uses 3 other files; get the full folder from GitHub.
name
analyzing-tls-certificate-transparency-logs
description
Queries Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT. Monitors newly issued certificates for typosquatting and brand impersonation using Levenshtein distance. Use for proactive phishing domain detection and certificate monitoring.
domain
cybersecurity
subdomain
security-operations
tags
certificate-transparency, ct-logs, crt-sh, phishing-detection, tls-monitoring, security-operations
version
1.0
author
mahipal
license
Apache-2.0
atlas_techniques
AML.T0073, AML.T0052
nist_csf
DE.CM-01, RS.MA-01, GV.OV-01, DE.AE-02
mitre_attack
T1583.001, T1566.002, T1598.003, T1583.006
mitre_f3.version
1.1

Analyzing TLS Certificate Transparency Logs

When to Use

  • When investigating security incidents that require analyzing tls certificate transparency logs
  • When building detection rules or threat hunting queries for this domain
  • When SOC analysts need structured procedures for this analysis type
  • When validating security monitoring coverage for related attack techniques

Prerequisites

  • Familiarity with security operations concepts and tools
  • Access to a test or lab environment for safe execution
  • Python 3.8+ with required dependencies installed
  • Appropriate authorization for any testing activities

Instructions

Query crt.sh Certificate Transparency database to find certificates issued for domains similar to your organization's brand, detecting phishing infrastructure.

python
from pycrtsh import Crtsh

c = Crtsh()
# Search for certificates matching a domain
certs = c.search("example.com")
for cert in certs:
    print(cert["id"], cert["name_value"])

# Get full certificate details
details = c.get(certs[0]["id"], type="id")

Key analysis steps:

  1. Query crt.sh for all certificates matching your domain pattern
  2. Identify certificates with typosquatting variations (Levenshtein distance)
  3. Flag certificates from unexpected CAs
  4. Monitor for wildcard certificates on suspicious subdomains
  5. Cross-reference with known phishing infrastructure

Examples

python
from pycrtsh import Crtsh
c = Crtsh()
certs = c.search("%.example.com")
for cert in certs:
    print(f"Issuer: {cert.get('issuer_name')}, Domain: {cert.get('name_value')}")

© mukul975, Apache-2.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 3 other files (scripts, references) in skills/analyzing-tls-certificate-transparency-logs of mukul975/Anthropic-Cybersecurity-Skills.

  • SKILL.md
  • LICENSE
  • references/api-reference.md
  • scripts/agent.py

Open the folder on GitHubat commit 54a7988

Compare with similar skills

Analyzing Tls Certificate Transparency Logs next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Analyzing Tls Certificate Transparency Logs compared with similar skills
SkillStarsUsed inTokensAuto-checkLicenceRepo updated
Analyzing Tls Certificate Transparency Logs this skillmukul975/Anthropic-Cybersecurity-Skills34k—~745Automated safety check: PassApache-2.0
Warp Vulnerability Triagewarpdotdev/warp65k1 repos~2.1kAutomated safety check: PassAGPL-3.0
mTLS Configurationwshobson/agents40k9 repos~588Automated safety check: PassMIT
Container Scanning with GrypeAgentSecOps/SecOpsAgentKit2201 repos~2.5kAutomated safety check: PassCustom licence
Snapshotboostsecurityio/poutine523—~214Automated safety check: PassApache-2.0
Dependency Triagecobusgreyling/loop-engineering11k—~300Automated safety check: PassMIT

Similar skills

  • Warp Vulnerability Triage

    warpdotdev/warp

    Gathers security findings from Dependabot, GCP container scanning, Docker Scout and Linear security issues, then triages and remediates them across Warp's repos and images.

    65k GitHub starsUsed in 1 repo~2.1k tokens
    SecurityAuto-check passed

  • mTLS Configuration

    wshobson/agents

    Walks through mutual TLS between services in a zero-trust setup: certificate hierarchy, rotation, a gradual PERMISSIVE-to-STRICT rollout and handshake debugging.

    40k GitHub starsUsed in 9 repos~588 tokens
    SecurityAuto-check passed

  • Container Scanning with Grype

    AgentSecOps/SecOpsAgentKit

    Scans container images, filesystems and SBOMs with Grype for known vulnerabilities, ranks them by CVSS, EPSS and CISA KEV, and wires scans into CI/CD thresholds.

    220 GitHub starsUsed in 1 repo~2.5k tokens
    SecurityAuto-check passed

  • Snapshot

    boostsecurityio/poutine

    Run snapshot regression tests after changes to OPA rules, scanners, analyzers, or formatters to detect output regressions.

    523 GitHub stars~214 tokensUpdated yesterday
    SecurityAuto-check passed

  • Dependency Triage

    cobusgreyling/loop-engineering

    Scans package manifests and lockfiles for outdated packages and known CVEs, then classifies each possible update as patch, minor, major or escalate-human for a dependency sweeper loop.

    11k GitHub stars~300 tokensUpdated today
    SecurityAuto-check passed

  • Container Security

    hardw00t/ai-security-arsenal

    Container and Kubernetes security assessment — image vulnerability scanning, SBOM diff analysis, K8s cluster auditing, RBAC privilege mapping, NetworkPolicy review, container escape testing, and…

    105 GitHub stars~2.8k tokensUpdated 5 mo ago
    SecurityAuto-check passed

More from mukul975/Anthropic-Cybersecurity-Skills

All 644 skills in this repo

  • Campaign Attribution Evidence Analysis

    mukul975/Anthropic-Cybersecurity-Skills

    Weighs infrastructure, TTP, malware code and timing evidence with the Diamond Model and competing hypotheses to reach a confidence-rated attribution.

    34k GitHub stars~2.3k tokensUpdated 1 mo ago
    Auto-check passed

  • Go Malware Analysis in Ghidra

    mukul975/Anthropic-Cybersecurity-Skills

    Walks through reverse engineering Go-compiled malware in Ghidra: parsing buildinfo and pclntab, recovering stripped function names and extracting dependencies.

    34k GitHub stars~2.8k tokensUpdated 1 mo ago
    Auto-check passed

  • LNK and Jump List Forensics

    mukul975/Anthropic-Cybersecurity-Skills

    Guides forensic analysis of Windows LNK shortcut files and Jump Lists with LECmd, JLECmd and manual parsing to show file access and program execution.

    34k GitHub stars~2.8k tokensUpdated 1 mo ago
    Auto-check passed

  • Malware Persistence Analysis with Autoruns

    mukul975/Anthropic-Cybersecurity-Skills

    Hunts Windows malware persistence with Sysinternals Autoruns, covering run keys, services, scheduled tasks and drivers, with baseline comparison.

    34k GitHub stars~1.2k tokensUpdated 1 mo ago
    Auto-check passed

  • NTFS MFT Deleted File Recovery

    mukul975/Anthropic-Cybersecurity-Skills

    Guides a Windows forensic examination of the NTFS Master File Table to recover deleted-file evidence, build timelines and spot timestomping.

    34k GitHub stars~2.7k tokensUpdated 1 mo ago
    Auto-check passed

  • Network Covert Channel Analysis

    mukul975/Anthropic-Cybersecurity-Skills

    Detects DNS tunneling, ICMP exfiltration and HTTP-based covert channels in packet captures and DNS logs when hunting for hidden command-and-control traffic.

    34k GitHub stars~2k tokensUpdated 1 mo ago
    Auto-check passed

Categories

Questions about Analyzing Tls Certificate Transparency Logs

What does Analyzing Tls Certificate Transparency Logs do?

Queries Certificate Transparency logs via crt.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT. Analyzing Tls Certificate Transparency Logs is an agent skill from mukul975/Anthropic-Cybersecurity-Skills.sh and pycrtsh to detect phishing domains, unauthorized certificate issuance, and shadow IT.

When should I use Analyzing Tls Certificate Transparency Logs?

Analyzing Tls Certificate Transparency Logs fits situations like: proactive phishing domain detection and certificate monitoring; tasks that involve Cloud networking; tasks that involve Supply chain security.

How do I install Analyzing Tls Certificate Transparency Logs in Claude Code?

Run `npx skills add mukul975/Anthropic-Cybersecurity-Skills --skill analyzing-tls-certificate-transparency-logs -a claude-code`. Or copy the skill folder (skills/analyzing-tls-certificate-transparency-logs in mukul975/Anthropic-Cybersecurity-Skills) into .claude/skills/analyzing-tls-certificate-transparency-logs in your project. Claude Code loads it when a task matches its description.

How do I install Analyzing Tls Certificate Transparency Logs in Codex?

Run `npx skills add mukul975/Anthropic-Cybersecurity-Skills --skill analyzing-tls-certificate-transparency-logs -a codex`. Or copy the skill folder (skills/analyzing-tls-certificate-transparency-logs in mukul975/Anthropic-Cybersecurity-Skills) into .agents/skills/analyzing-tls-certificate-transparency-logs in your project. Codex loads it when a task matches its description.

Can I use Analyzing Tls Certificate Transparency Logs in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add mukul975/Anthropic-Cybersecurity-Skills --skill analyzing-tls-certificate-transparency-logs -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/analyzing-tls-certificate-transparency-logs, .gemini/skills/analyzing-tls-certificate-transparency-logs, .github/skills/analyzing-tls-certificate-transparency-logs and .opencode/skills/analyzing-tls-certificate-transparency-logs in your project.

What does Analyzing Tls Certificate Transparency Logs need to run?

Going by SKILL.md and its folder, Analyzing Tls Certificate Transparency Logs needs Python for the scripts in its folder. Our summary lists: Python 3.

Does Analyzing Tls Certificate Transparency Logs access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Analyzing Tls Certificate Transparency Logs safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.

What licence does Analyzing Tls Certificate Transparency Logs use?

Analyzing Tls Certificate Transparency Logs is published under the Apache-2.0 licence (declared in SKILL.md). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Analyzing Tls Certificate Transparency Logs use?

About 745 tokens (SKILL.md is roughly 3k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 378 tokens, read only when the agent opens those files.

What are the alternatives to Analyzing Tls Certificate Transparency Logs?

Skills that share tags, products or a category with Analyzing Tls Certificate Transparency Logs: Warp Vulnerability Triage (warpdotdev/warp, 65k stars), mTLS Configuration (wshobson/agents, 40k stars), Container Scanning with Grype (AgentSecOps/SecOpsAgentKit, 220 stars) and Snapshot (boostsecurityio/poutine, 523 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Analyzing Tls Certificate Transparency Logs?

mukul975 (a GitHub user) maintains it in mukul975/Anthropic-Cybersecurity-Skills, which has 34,116 GitHub stars. The repository holds 644 skills in this directory. The repository was last updated on August 31, 2026.

Source: mukul975/Anthropic-Cybersecurity-Skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.