github.com/crewjam/saml is a saml library for the go language. In affected versions the package does not validate the ACS Location URI according to the SAML binding being parsed. If abused, this flaw allows attackers to register malicious Service Providers at the IdP and inject Javascript in the ACS endpoint definition, achieving Cross-Site-Scripting (XSS) in the IdP context during the redirection at the end of a SAML SSO Flow. Consequently, an attacker may perform any authenticated action as the victim once the victim’s browser loaded the SAML IdP initiated SSO link for the malicious service provider. Note: SP registration is commonly an unrestricted operation in IdPs, hence not requiring particular permissions or publicly accessible to ease the IdP interoperability. This issue is fixed in version 0.4.14. Users unable to upgrade may perform external validation of URLs provided in SAML metadata, or restrict the ability for end-users to upload arbitrary metadata.

Node-SAML is a SAML library not dependent on any frameworks that runs in Node. The lack of checking of current timestamp allows a LogoutRequest XML to be reused multiple times even when the current time is past the NotOnOrAfter. This could impact the user where they would be logged out from an expired LogoutRequest. In bigger contexts, if LogoutRequests are sent out in mass to different SPs, this could impact many users on a large scale. This issue was patched in version 4.0.5.

The crewjam/saml go library contains a partial implementation of the SAML standard in golang. Prior to version 0.4.13, the package's use of `flate.NewReader` does not limit the size of the input. The user can pass more than 1 MB of data in the HTTP request to the processing functions, which will be decompressed server-side using the Deflate algorithm. Therefore, after repeating the same request multiple times, it is possible to achieve a reliable crash since the operating system kills the process. This issue is patched in version 0.4.13.

php-saml-sp before 1.1.1 and 2.x before 2.1.1 allows reading arbitrary files as the webserver user because resolving XML external entities was silently enabled via \LIBXML_DTDLOAD | \LIBXML_DTDATTR.

The crewjam/saml go library prior to version 0.4.9 is vulnerable to an authentication bypass when processing SAML responses containing multiple Assertion elements. This issue has been corrected in version 0.4.9. There are no workarounds other than upgrading to a fixed version.

node SAML is a SAML 2.0 library based on the SAML implementation of passport-saml. 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. Users should upgrade to node-saml version 4.0.0-beta5 or newer. Disabling SAML authentication may be done as a workaround.

Passport-SAML is a SAML 2.0 authentication provider for Passport, the Node.js authentication library. 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. Users should upgrade to passport-saml version 3.2.2 or newer. The issue was also present in the beta releases of `node-saml` before version 4.0.0-beta.5. If you cannot upgrade, disabling SAML authentication may be done as a workaround.

Passport-SAML is a SAML 2.0 authentication provider for Passport, the Node.js authentication library. Prior to version 3.1.0, a malicious SAML payload can require transforms that consume significant system resources to process, thereby resulting in reduced or denied service. This would be an effective way to perform a denial-of-service attack. This has been resolved in version 3.1.0. The resolution is to limit the number of allowable transforms to 2.

A signature verification vulnerability exists in crewjam/saml. This flaw allows an attacker to bypass SAML Authentication. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.