Signature bypass via multiple root elements

Impact

A remote attacker may be able to bypass SAML authentication on a website using passport-saml. A successful attack requires that the attacker is in possession of an arbitrary IDP signed XML element. Depending on the IDP used, fully unauthenticated attacks (e.g without access to a valid user) might also be feasible if generation of a signed message can be triggered.

Patches

Users should upgrade to node-saml v4.0.0-beta5 or newer.

Workarounds

Disable SAML authentication.

References

Are there any links users can visit to find out more?

For more information

If you have any questions or comments about this advisory:

• Open a discussion in the node-saml repo

Credits

• Felix Wilhelm of Google Project Zero