The cBioPortal for Cancer Genomics provides visualization, analysis, and download of large-scale cancer genomics data sets. When running a publicly exposed proxy endpoint without authentication, cBioPortal could allow someone to perform a Server Side Request Forgery (SSRF) attack. Logged in users could do the same on private instances. A fix has been released in version 6.0.12. As a workaround, one might be able to disable `/proxy` endpoint entirely via, for example, nginx.