GHSA-f4g9-h89h-jgv9 SAML XML Signature wrapping in PySAML2

• PyPI pysaml2: < 6.5.0 → fixed in 6.5.0

Impact All users of pysaml2 that use the default `CryptoBackendXmlSec1` backend and need to verify signed SAML documents are impacted. `pysaml2 <= 6.4.1` does not validate the SAML document against an XML schema. This allows invalid XML documents to trick the verification process, by presenting elements with a valid signature inside elements whose content has been malformed. The verification is offloaded to `xmlsec1` and `xmlsec1` will not validate every signature in the given document, but only the first it finds in the given scope. Patches Users should upgrade to pysaml2 `v6.5.0`. Workarounds No workaround provided at this point. References No references provided at this point. Credits • Victor Schönfelder Garcia (isits AG International School of IT Security) • Juraj Somorovsky (Paderborn University) • Vladislav Mladenov (Ruhr University Bochum) For more information If you have any questions or comments about this advisory: • Open an issue in pysaml2 • Email us at the incident-response address