This is a rebuild as described in #1 and #2
For example
$ sudo dnf install fedora-packager redhat-lsb
$ rpmdev-setuptree
$ cd ~/rpmbuild/SOURCES
$ curl -fSL https://github.com/spotsnel/AltRPMS-KasmVNC/releases/download/1.3.2/source-kasmvnc.fedora_forty.[arch].rpm -o kasmvnc.fedora_forty.aarch64.rpm
$ rpm2archive kasmvnc.fedora_forty.[arch].rpm
$ mv kasmvnc.fedora_forty.[arch].rpm.tgz kasmvnc.fedora_forty.tar.gz
$ cd ../SPECS
$ curl -fSL https://github.com/spotsnel/AltRPMS-KasmVNC/releases/download/1.3.2/kasmvncserver.spec -o modified-kasmvncserver.spec
$ cd ..
$ rpmbuild -ba SPECS/modified-kasmvncserver.spec
Note: the source packages are distributed at https://github.com/kasmtech/KasmVNC/releases