3 ms·

> That's why I'm careful not to include allow-same-origin in the sandbox attribute It doesn't matter. I just said there is no combination of CSP or the iframe

• simonw 4mo ago
  If that's true then my project is fatally flawed and I need to stop distributing it. I'm not convinced it's true - I've been thinking about this for months, and building experimental prototypes to help me get to the combination that I think makes sense. Can you describe an exploit that the combination I'm using of iframe sandbox= srcdoc= with an injected meta CSP tag doesn't handle? Would moving the untrusted content to be served from a separate domain entirely close the hole? (In case it's not clear the iframe sandbox= is the bit that's doing most of the work here - the CSP stuff is there mainly to protect against malicious apps that deliberately exfiltrate stolen private data.)
  • cxr 4mo ago
    > Would moving the untrusted content to be served from a separate domain entirely close the hole? Yes.