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SAML attacks

SSO XML that is trusted more than the HTTP layer. Recipient, Audience, Destination, and wrapping are the gadgets. Pair with XXE on the same parser. Test tenant only.

Playbooks

  • SAML / SSO Attacks - SAML is XML plus cryptography plus a pile of libraries that disagree. Signature wrap and XXE still show up.

Gadgets

  • XML external entity / DTD fetch - A parser that loads a DTD from a URL you control is at least SSRF. File read and billion-laughs are extra, not the first proof.
  • SAML ACS / recipient confusion - If the SP accepts an assertion meant for another ACS, or does not bind Recipient / Audience / Destination, you mint a session.

Payloads

  • SAML assertion probes - Lab or test-tenant only. Recipient, Audience, Destination, and comment wrapping. Pair with the XXE canary on the same ACS parser.

Bypasses

  • XXE parser still fetches - Prove the parser resolves an external identifier with a canary. Do not file-read or hit metadata first.
  • SAML ACS and wrapping - Test on an IdP/SP pair you control or a program test tenant. Signature wrapping and Recipient mismatch are parser bugs.

Questions

Golden SAML vs wrapping?

Golden SAML is an IdP key leak. Wrapping is a parser bug. Do not mix the reports.

Can I replay production assertions?

Only on an IdP and SP you control, or a program test tenant.

This page is the public form of hunt_brief("saml") on the MCP connector. Authorized testing only.