Spectre does not allow write access to unprivileged memory; you need another exploit for that. Spectre allows read access to essentially all of the containing p

Spectre does not allow write access to unprivileged memory; you need another exploit for that. Spectre allows read access to essentially all of the containing process's address space. This is enough for just leaking secrets, but can also assist with other vulnerabilities, e.g. reversing address space randomization in order to figure out where to write in memory with the other vulnerability. It makes all write exploits more dangerous.