Skills

Hunt Auth Bypass

Hunting skill for auth bypass vulnerabilities.

Install

npx skills add elementalsouls/Claude-BugHunter --skill hunt-auth-bypass -g -a claude-code -y
Category
Design
Updated
3d ago
License
MIT
Context cost
Mediumabout 3,000 tokens
Runs scripts
No, instructions only

What it does

Hunting skill for auth bypass vulnerabilities. Built from 12 public bug bounty reports across SAML XSW / parser-differential (GitHub Enterprise CVE-2025-25291/25292), SAML signature stripping (Uber, Rocket.Chat, samlify CVE-2025-47949), SAML domain enforcement bypass via control characters (HackerOne 2024), partner-portal cross-IdP assertion reuse (Slack), WordPress XMLRPC bypassing SSO (Uber), JWT alg-confusion HS256/RS256 (Jitsi), JWT signature-validation skip (Linktree, Newspack), and token-audience confusion (Argo CD CVE-2023-22482). For standalone JWT signature/crypto forging (alg:none, key confusion, kid/jku) see hunt-jwt-crypto; this skill covers JWT only inside SSO/SAML/token-trust bypass chains. SAML assertion-layer attacks (XSW, comment injection, signature stripping, XXE-in-assertion) are owned by hunt-saml; this skill owns the broader cross-protocol auth-bypass taxonomy. Use when hunting auth bypass, see the Legacy-Protocol Matrix for branded-UI vs legacy-endpoint patterns.

Crown Jewel Targets

Auth bypass is consistently one of the highest-paying vulnerability classes in bug bounty because it directly violates the most fundamental security control. High-value targets include:

  • SSO/SAML implementations at enterprise SaaS companies (Slack, Okta, OneLogin integrations), payouts regularly in the $5K, $25K+ range
  • Admin panels and partner/internal portals, subdomain-separated admin surfaces like partners.shopify.com, admin.company.com
  • Third-party auth plugin integrations, WordPress plugins (OneLogin, WP-SAML-Auth), Drupal SSO modules, any CMS with pluggable auth
  • XMLRPC endpoints on WordPress, often forgotten, bypasses standard WP auth flows entirely
  • OAuth callback flows, state parameter mishandling, redirect_uri mismatches
  • API authentication layers, especially where auth was bolted on after the fact

Asset priority: Targets with federated identity (SAML, OAuth, OIDC) connected to large user populations. Partner/reseller portals are particularly juicy because they often have elevated permissions and less security scrutiny than the main product.


SSH certificate-authority trust forgery (Git-hosting / enterprise platforms)

When an org or instance registers an SSH certificate authority, cert principals may not be bound server-side to the requesting identity, a member can mint a cert asserting another user's principal and authenticate as them (e.g. modify another user's resource given only its URL). Add SSH-CA trust to the auth-surface list on Git-hosting targets; niche/platform-specific. Disclosed: reports/1901040.

Attack Surface Signals

URL patterns to hunt:

/xmlrpc.php
/wp-login.php
/saml/
/sso/
/auth/saml/callback
/oauth/callback
/partners.*
/admin.*
/?wc-api=
/api/v*/auth
/login?redirect=
/accounts/login
Read the whole SKILL.md on GitHub

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