The example syntax is specific to the Xalan XSLT engine, but this approach is valid for most XSLT engines.The example calls "os:exec" as a user-defined extension, which is mapped to the Java lang.
safedatingsite com - And non validating parsers with
The scope of this denial of service attack is greatly reduced when following the best practices described above, since it is unlikely that an authenticated user would include this kind of transform.
XSLT transforms should only be processed for References, and not for As discussed further, below, support for XSLT transforms may also expose the signature processor or consumer to further risks in regard to external references or modified approvals.
However, they do not constitute a normative update to the XML Signature specification, and might not be applicable in certain situations.
This Working Group Note publication updates the references that have changed since the previous Working Group Note publication (diff).
This document was published by the XML Security Working Group as a Working Group Note.
If you wish to make comments regarding this document, please send them to [email protected](subscribe, archives). Publication as a Working Group Note does not imply endorsement by the Membership.
Runtime.exec() method which can execute any program the process has the rights to run.
While the example calls the shutdown command, one should expect more painful attacks if a series of attack signatures are allowed.
As will be seen below, certain kinds of transforms may require an enormous amount of processing time and certain external URI references can lead to possible security violations.
One recommendation for implementing the XML Signature Recommendation is to first "authenticate" the signature, before running any of these dangerous operations. However an implementation may still choose to disallow these operations even in step 3, if the party is not trusted to perform them.
This is a draft document and may be updated, replaced or obsoleted by other documents at any time.