What exactly does "RCE inside sandbox" describe that goes beyond "the webpage can supply arbitrary JavaScript and the JavaScript engine executes it", but is still isolated from the system?
Chrome runs webpages in individual sandbox processes with very low privileges, as a defense-in-depth strategy. It generally requires at least two exploits to actually affect a user--first, get RCE in a sandboxed process, then find a separate vulnerability that lets you escape the sandbox process entirely. For this bug to have actually been used in the wild, there was almost certainly a second bug as well.
It means it can execute native code inside the sandbox, as opposed to Javascript. While still sandboxed, this lets it access some parts of the attack surface that JS would not have been able to, some of which may have other exploits that allow escaping the rest of the way.
I think people would like to understand what the "sandbox" is here and what isolation does it provide, is it an unprivileged process? something chromium specific? a v8/JS thing? etc.
Memory isolation having one tab or account open on your bank and another on this page does not mean it could leak across the sandbox and steal bank account details but anything inside of your general page content can be lost
This doesn't affect the score though, the reason there's 1.2 points less than the max is because there is a Required User Interaction. The user needs to visit a specific html page.
Even with the sandbox protection layer, the rest of the parameters are maxed out.
I don't know why this is being downvoted. This is called malvertising and its one of the most significant vectors for exploiting a vulnerability like this. Its happened multiple times over the last two decades.
My read of Google's disclosure is that there is likely no known escape from the sandbox. I don't agree this would be reported this way just because "user action" like "using web browser" is required. Even if this individual CVE is correctly an 8.8 there would be a critical assessment of a known chain. The only reason there wouldn't be, would be if the other vulnerability is known to Google but has no patch yet.
What exactly does "RCE inside sandbox" describe that goes beyond "the webpage can supply arbitrary JavaScript and the JavaScript engine executes it", but is still isolated from the system?
Chrome runs webpages in individual sandbox processes with very low privileges, as a defense-in-depth strategy. It generally requires at least two exploits to actually affect a user--first, get RCE in a sandboxed process, then find a separate vulnerability that lets you escape the sandbox process entirely. For this bug to have actually been used in the wild, there was almost certainly a second bug as well.
It means it can execute native code inside the sandbox, as opposed to Javascript. While still sandboxed, this lets it access some parts of the attack surface that JS would not have been able to, some of which may have other exploits that allow escaping the rest of the way.
It means it can execute arbitrary machine code in the sandbox.
I think people would like to understand what the "sandbox" is here and what isolation does it provide, is it an unprivileged process? something chromium specific? a v8/JS thing? etc.
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Okay, and why is that more of a security risk than executing arbitrary JavaScript in the sandbox?
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> It means it can execute arbitrary machine code in the sandbox.
Well which is precisely why we have sandboxes.
To me "executing arbitrary code in the sandbox" is similar to "I don't give a flying fuck for it's what a sandbox is for".
More information is needed. As someone commented: this has to be paired with at least another exploit to make anything remotely useful.
A sandbox is a sandbox. We want to understand how "code running in a sandbox" is "actively exploited".
Memory isolation having one tab or account open on your bank and another on this page does not mean it could leak across the sandbox and steal bank account details but anything inside of your general page content can be lost
This doesn't affect the score though, the reason there's 1.2 points less than the max is because there is a Required User Interaction. The user needs to visit a specific html page.
Even with the sandbox protection layer, the rest of the parameters are maxed out.
what is online ad networks for $100, alex
I don't know why this is being downvoted. This is called malvertising and its one of the most significant vectors for exploiting a vulnerability like this. Its happened multiple times over the last two decades.
My read of Google's disclosure is that there is likely no known escape from the sandbox. I don't agree this would be reported this way just because "user action" like "using web browser" is required. Even if this individual CVE is correctly an 8.8 there would be a critical assessment of a known chain. The only reason there wouldn't be, would be if the other vulnerability is known to Google but has no patch yet.