Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to versions 2.1.13 and 2.2.13, the "Deno.env.toObject" method ignores any variables listed in the "--deny-env" option of the "deno run" command. When looking at the documentation of the "--deny-env" option this might lead to a false impression that variables listed in the option are impossible to read. Software relying on the combination of both flags to allow access to most environment variables except a few sensitive ones will be vulnerable to malicious code trying to steal secrets using the "Deno.env.toObject()" method. Versions 2.1.13 and 2.2.13 contains a patch.