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Bypassing anti-incognito detection in Google Chrome

mishravikas.com

11–20 of 114 posts

Re: Bypassing anti-incognito detection in Google Chrome

#11
post #3

there is only one way to get around this. incognito mode needs to emulate all system resources without actually making them available. even without that consideration, for things like disk storage, there is no reason[1] why incognito mode should have less access than normal mode. all websites should function as normal. the only difference is that in incognito mode everything is wiped once it is closed, and nothing is…

If Chrome encrypted the data it wrote to disk, it can throw away the encryption key and delete the file when you close the incognito window, thus giving you access to the disk securely.

Any sort of file system imprint would at least leave a trace that incognito had been used. I’m not sure how much of a problem at is, and how much of a trace it currently leaves.

Re: Bypassing anti-incognito detection in Google Chrome

#12
post #6

Is there any legitimate reason to allow arbitrary web apps to use gigabytes of space on my precious SSD, especially on mobile devices? I'm becoming increasingly wary of web apps having all sorts of access to things outside of the browser, sometimes without explicit permission. Browsers should limit every app to the same amount, perhaps 100MB, or maybe even 10MB. Apps that need more should ask for permission.

I believe the “Quota Management API” [1] the author is using is an experimental API for the browser to request more space, beyond the default maximum of 5MB.

[1] https://developer.chrome.com/apps/offline_storage

Re: Bypassing anti-incognito detection in Google Chrome

#13
post #3

there is only one way to get around this. incognito mode needs to emulate all system resources without actually making them available. even without that consideration, for things like disk storage, there is no reason[1] why incognito mode should have less access than normal mode. all websites should function as normal. the only difference is that in incognito mode everything is wiped once it is closed, and nothing is…

If Chrome encrypted the data it wrote to disk, it can throw away the encryption key and delete the file when you close the incognito window, thus giving you access to the disk securely.

> thus giving you access to the disk securely

The amount of encrypted data could be a side channel

Re: Bypassing anti-incognito detection in Google Chrome

#15
post #6

Is there any legitimate reason to allow arbitrary web apps to use gigabytes of space on my precious SSD, especially on mobile devices? I'm becoming increasingly wary of web apps having all sorts of access to things outside of the browser, sometimes without explicit permission. Browsers should limit every app to the same amount, perhaps 100MB, or maybe even 10MB. Apps that need more should ask for permission.

I believe the “Quota Management API” [1] the author is using is an experimental API for the browser to request more space, beyond the default maximum of 5MB. [1] https://developer.chrome.com/apps/offline_storage

[deleted]

Re: Bypassing anti-incognito detection in Google Chrome

#16

Earlier quoted context omitted.

If Chrome encrypted the data it wrote to disk, it can throw away the encryption key and delete the file when you close the incognito window, thus giving you access to the disk securely.

Any sort of file system imprint would at least leave a trace that incognito had been used. I’m not sure how much of a problem at is, and how much of a trace it currently leaves.

there are many mundane reasons to use incognito mode. and the system would work in a way that the user will not even know the decryption key since it can be generated on the fly for each session.

the browser could even encrypt all their data by default. (but for non-incognito mode with a known key) it could then write the normal and incognito data in such a way that you can't even see that there is incognito data in there if you don't have the incognito key

Re: Bypassing anti-incognito detection in Google Chrome

#17
post #6

Is there any legitimate reason to allow arbitrary web apps to use gigabytes of space on my precious SSD, especially on mobile devices? I'm becoming increasingly wary of web apps having all sorts of access to things outside of the browser, sometimes without explicit permission. Browsers should limit every app to the same amount, perhaps 100MB, or maybe even 10MB. Apps that need more should ask for permission.

I believe the “Quota Management API” [1] the author is using is an experimental API for the browser to request more space, beyond the default maximum of 5MB. [1] https://developer.chrome.com/apps/offline_storage

[deleted]

Re: Bypassing anti-incognito detection in Google Chrome

#18

Earlier quoted context omitted.

If Chrome encrypted the data it wrote to disk, it can throw away the encryption key and delete the file when you close the incognito window, thus giving you access to the disk securely.

Any sort of file system imprint would at least leave a trace that incognito had been used. I’m not sure how much of a problem at is, and how much of a trace it currently leaves.

What about swap space used on the disk by the OS, transparent to the application? Is that also a concern for “file system imprint”? What’s the threat model here? The application would have to use RAM that’s never swapped for storing this sort of information. That would make it quite heavy.

Re: Bypassing anti-incognito detection in Google Chrome

#19
post #6

Is there any legitimate reason to allow arbitrary web apps to use gigabytes of space on my precious SSD, especially on mobile devices? I'm becoming increasingly wary of web apps having all sorts of access to things outside of the browser, sometimes without explicit permission. Browsers should limit every app to the same amount, perhaps 100MB, or maybe even 10MB. Apps that need more should ask for permission.

I believe the “Quota Management API” [1] the author is using is an experimental API for the browser to request more space, beyond the default maximum of 5MB. [1] https://developer.chrome.com/apps/offline_storage

On the contrary its on active development, The one you are referring to "Quota Management API" [1] is not what's being used in the article. It's the "Storage" API's Estimate method [2] which is in active development. [1]https://w3c.github.io/quota-api/ [2]https://storage.spec.whatwg.org

Re: Bypassing anti-incognito detection in Google Chrome

#20
post #18

Earlier quoted context omitted.

Any sort of file system imprint would at least leave a trace that incognito had been used. I’m not sure how much of a problem at is, and how much of a trace it currently leaves.

What about swap space used on the disk by the OS, transparent to the application? Is that also a concern for “file system imprint”? What’s the threat model here? The application would have to use RAM that’s never swapped for storing this sort of information. That would make it quite heavy.

I think chrome devs want to limit the "file system imprint" as much as possible to enforce "no-history in incognito". There's been some discussions on finding a way around crash reporting in incognito session which stores the dump in the disk, and to my knowledge this is the only violation of this policy. [1]https://bugs.chromium.org/p/chromium/issues/detail?id=876270...
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