xmlsec1 1.2.21 removed Soap support which Lasso utilizes (e.g. xmlSecSoap* symbols). xmlsec1 1.2.22 restored Soap for Lasso xmlsec1 1.2.24 deprecated Soap xmlsec1 1.2.25 added --enable-soap configure option to build soap support, however soap is still deprecated and will be removed in a future release. Therefore the only sensible thing is to remove Lasso's dependence on xmlSecSoap and re-implement the functionality in Lasso.
lasso-2.5.1-13.fc28 has been submitted as an update to Fedora 28. https://bodhi.fedoraproject.org/updates/FEDORA-2018-3fcce95800
lasso-2.5.1-13.fc28 has been pushed to the Fedora 28 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2018-3fcce95800
lasso-2.5.1-13.fc28 has been pushed to the Fedora 28 stable repository. If problems still persist, please make note of it in this bug report.