
Analyzing Certificate Transparency For Phishing
Hunt newly issued TLS certificates that impersonate your brand or customers by querying Certificate Transparency data for phishing infrastructure.
Overview
Analyzing Certificate Transparency for Phishing is an agent skill for the Ship phase that helps discover phishing domains by analyzing CT log certificate issuances.
Install
npx skills add https://github.com/mukul975/anthropic-cybersecurity-skills --skill analyzing-certificate-transparency-for-phishingWhat is this skill?
- Focuses on Certificate Transparency feeds to surface lookalike and fraudulent domains
- Fits Anthropic cybersecurity skills bundle for agent-guided threat hunting
- Supports proactive detection before users report credential-harvesting sites
- Pairs with domain monitoring and takedown workflows for indie SaaS founders
- Apache 2.0 licensed collection item—verify local SKILL.md for exact query steps
Adoption & trust: 1 installs on skills.sh; 14.9k GitHub stars; 2/3 security scanners passed (skills.sh audits); trending (+100% hot-view momentum).
What problem does it solve?
You worry attackers are minting TLS certs for domains that look like yours, but you do not have a process to monitor CT logs.
Who is it for?
Founders shipping customer-facing SaaS who need lightweight brand-abuse detection without an enterprise SOC.
Skip if: Teams with no public brand or domain exposure, or those who already have managed CT monitoring and SOC playbooks.
When should I use this skill?
When monitoring brand impersonation, investigating reported phishing URLs, or adding CT-based domain discovery to your security checklist.
What do I get? / Deliverables
You obtain a prioritized list of suspicious certificates or hostnames to investigate, block, or escalate for takedown.
- Suspicious hostname or certificate candidate list
- Investigation notes for block or takedown
Recommended Skills
Journey fit
Certificate Transparency review is a pre-release and ongoing assurance activity aligned with hardening before and after you ship internet-facing properties. Phishing domain discovery via CT logs is classic application and brand security work in the security subphase.
How it compares
Agent-guided CT hunting skill—not a replacement for managed brand-protection SaaS or full pentest engagements.
Common Questions / FAQ
Who is analyzing-certificate-transparency-for-phishing for?
Solo builders and small teams defending a public brand or login surface who want agent help reviewing Certificate Transparency for impersonation domains.
When should I use analyzing-certificate-transparency-for-phishing?
During Ship security hardening, after launch when monitoring abuse, or when validating that a reported phishing URL is tied to a fresh cert.
Is analyzing-certificate-transparency-for-phishing safe to install?
It may call external CT APIs or run network queries; review the Security Audits panel on this page and the full SKILL.md before granting network permissions.
SKILL.md
READMESKILL.md - Analyzing Certificate Transparency For Phishing
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