SharpCell.Grid shows workbooks that often come from untrusted sources. A file that makes it crash the process, hang or use unbounded memory is a security issue; one inside the formula engine or the .xlsx reader belongs to SharpCell.

Report privately through GitHub: Security → Report a vulnerability on https://github.com/ifmelate/SharpCell.Grid. Do not open a public issue. Attach the smallest file that shows the problem, and do not send confidential workbooks.

The project has one maintainer working in spare time. Expect an answer within two weeks; a fix ships in a new release of the latest minor version.

Only the latest released version gets fixes.