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0 pointsrank04y ago0 comments

Ah thanks for pointing that out.

But nonetheless, this is useful technology for a malicious actor.

For example, a functioning http server would enable an http proxy that could intercept/modify requests made from the client no?

Now I can add headers to requests made by an html form submit. This might allow for more potent csrf attacks, or circumvention of controls like the HttpOnly cookie flag.

Can I use a victims browser as a c2 server now? I bet with some brainstorming we could come up with some creative offensive capabilities using this technology.

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rezonant4y ago

No, you can't start a web server within Browsix that can accept connections from outside Browsix.

Just like you can't do that in regular JavaScript in the browser.

rank0OP4y ago

I see. So an form submit POST request could not actually be sent to Browsix?

rezonant4y ago

That's right, unless the form was running in Browsix, or I suppose at least the same browsing context (ie same origin on the same browser instance on the same computing device) since you could emulate submission across multiple tabs of the same website using something like the BroadcastChannel API[1]

[1] https://developer.mozilla.org/en-US/docs/Web/API/Broadcast_C...

EDIT: To be clear, this would require effort (TM)- the form would need to have a Javascript onsubmit handler and use preventDefault to stop the browser itself from handling it in order to facilitate that

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0 pointsrank04y ago0 comments

Ah thanks for pointing that out.

But nonetheless, this is useful technology for a malicious actor.

For example, a functioning http server would enable an http proxy that could intercept/modify requests made from the client no?

Now I can add headers to requests made by an html form submit. This might allow for more potent csrf attacks, or circumvention of controls like the HttpOnly cookie flag.

Can I use a victims browser as a c2 server now? I bet with some brainstorming we could come up with some creative offensive capabilities using this technology.

0 comments

rezonant4y ago

No, you can't start a web server within Browsix that can accept connections from outside Browsix.

Just like you can't do that in regular JavaScript in the browser.

rank0OP4y ago

I see. So an form submit POST request could not actually be sent to Browsix?

rezonant4y ago

[1] https://developer.mozilla.org/en-US/docs/Web/API/Broadcast_C...

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j / k navigate · click thread line to collapse