Scan a source tree for weak cryptographic primitives: MD5 / SHA-1 used for security purposes, DES / 3DES / RC4 ciphers, ECB block mode, custom-built crypto (XOR loops, hand-rolled HMAC), hardcoded IVs, predictable random (Math.random / java.util.Random for crypto seeds), missing certificate verification (verify=False, rejectUnauthorized: false). Use when: pre-merge gate on crypto-touching code, audit before SOC2 / PCI assessment, post-incident review when "we found a weakness in our token signing." Threshold: any call to a known-weak algorithm with non-test context, OR cert verification explicitly disabled, OR a custom crypto loop pattern. Trigger with: "scan weak crypto", "find MD5 usage", "check ECB mode", "audit ssl verify", "weak random".
Detecting Weak Cryptography includes a dedicated installation section; worked examples; at least one code block. The SKILL.md is on the shorter side at about 534 words.
Detecting Weak Cryptography sits in the Security category under the threat-hunting sub-topic in the ClaudSkills catalog. There are 10 related skills indexed alongside it; comparing a few before installing usually reveals which fits your workflow best.
These notes are auto-generated from features detected in the SKILL.md file and from this catalog's structure — they aren't part of the source repository.
What this skill does
Detecting Weak Cryptography is a community-contributed Claude Code skill in the threat-hunting sub-category. It ships as a SKILL.md file that Claude Code auto-discovers under ~/.claude/skills/detecting-weak-cryptography/ and loads when your prompt matches the skill's trigger.
When to invoke it: Use when: pre-merge gate on crypto-touching code, audit before SOC2 / PCI assessment, post-incident review when "we found a weakness in our token signing." Threshold: any call to a known-weak algorithm with non-test context, OR cert verification explicitly disabled, OR a custom crypto loop pattern.
Who uses this skill
The Detecting Weak Cryptography Claude Code skill is built for security engineers, penetration testers, DevSecOps practitioners, and development teams hardening codebases and infrastructure. It's part of ClaudSkills (also referred to as Claude Skills or Claude Code Skills) — the open community-curated registry of 164,000+ SKILL.md files for Anthropic's Claude Code agent and the wider Claude ecosystem (Claude API, Claude Agent SDK).
Or just download SKILL.md directly and drop it into ~/.claude/skills/detecting-weak-cryptography/. Claude Code auto-discovers it on next session.
Skills live at ~/.claude/skills/detecting-weak-cryptography/SKILL.md on macOS/Linux, or %USERPROFILE%\.claude\skills\detecting-weak-cryptography\SKILL.md on Windows. See the full install guide for step-by-step instructions.
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📱 Install from your phone or desktop Telegram
Open @claudskills_bot on Telegram, tap Open Desktop App, and the desktop app installs this skill for you. Or share the bot link with a colleague — they get the same one-tap install. Learn more →
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One-click install via the desktop app
The ClaudSkills desktop app installs any skill directly into ~/.claude/skills/ with one click — no terminal required. Pro starts at $9/mo or $149 lifetime.
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How do I install the Detecting Weak Cryptography Claude Code skill?
Install via the ClaudSkills desktop app (one click) or copy SKILL.md from the source repository to ~/.claude/skills/detecting-weak-cryptography/SKILL.md and restart Claude Code. Both flows are detailed at claudskills.com/install/.
What does the Detecting Weak Cryptography skill do?
Scan a source tree for weak cryptographic primitives: MD5 / SHA-1 used for security purposes, DES / 3DES / RC4 ciphers, ECB block mode, custom-built crypto (XOR loops, hand-rolled HMAC), hardcoded IVs, predictable random (Math.random / java.util.Random for crypto seeds), missing certificate verification (verify=False, rejectUnauthorized: false). Use when: pre-merge gate on crypto-touching code, audit before SOC2 / PCI assessment, post-incident review when "we found a weakness in our token signing." Threshold: any call to a known-weak algorithm with non-test context, OR cert verification explicitly disabled, OR a custom crypto loop pattern. Trigger with: "scan weak crypto", "find MD5 usage", "check ECB mode", "audit ssl verify", "weak random".
Is this skill free to install?
Yes. ClaudSkills is an open registry — every skill keeps its source repository's license, and manual install via copy is free. ClaudSkills Pro ($9/mo, $79/yr, or $149 one-time) adds one-click install via the desktop app and a multi-signal Quality Score.
When should I use the Detecting Weak Cryptography skill?
Use Detecting Weak Cryptography when your Claude Code task falls under the Security category — specifically in the threat hunting area. Claude Code auto-discovers installed skills and invokes the right one based on the task description, so you can also ask Claude directly (e.g. "use Detecting Weak Cryptography" or describe the task and let Claude pick). Browse related skills at /category/security/.
What is a Claude Code skill and how does the Detecting Weak Cryptography skill fit in?
A Claude Code skill is a SKILL.md file that lives under ~/.claude/skills/<name>/ and tells the Claude Code CLI agent how to perform a specific task (instructions, prompts, allowed tools). Skills are auto-discovered at session start. Detecting Weak Cryptography is one of 67,000+ skills indexed in the open ClaudSkills catalog, classified under the Security category. Learn more at /learn/what-is-a-claude-skill/.
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Claude™ is a trademark of Anthropic PBC. ClaudSkills (also referred to as Claude Skills or Claude Code Skills Catalog) is an independent community-curated registry of SKILL.md files, not affiliated with, endorsed by, or sponsored by Anthropic.
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