2 ms·

I personally just upload them to google drive. It would be a serious pwn if they could somehow still do a compromise through google drive.

gleenn 9mo ago
Do you have any specifics on what Drive does? Any examples of it fixing embedded virii? Or is this blind assumption?
- akersten 9mo ago
  I assume they mean "upload to drive and use the web based reader to view the PDF," not "upload to drive and download it again"
  - gleenn 9mo ago
    And what special sauce does the web preview use? At some point, someone has to actually parse and process the data. I feel like on a tech site like Hacker News, speculating that Google has somehow done a perfect job of preventing malicious PDFs beckons the question: how do you actually do that and prove that it's safe? And is that even possible in perpetuity?
    - deleted 9mo ago
      [deleted]
    - dfajgljsldkjag 9mo ago
      It's an image sent from Google.
    - fc417fc802 9mo ago
      > how do you actually do that and prove that it's safe? Obviously you can't. You assume it's best in class based on various factors including the fact that this is the same juggernaut that runs project zero. They also somehow manage to secure their cloud offering against malicious clients so presumably they can manage to parse a pdf to an image without getting pwned. It would certainly be interesting to know what their internal countermeasures are but I don't know if that's publicized or not.
    - nl 9mo ago
      It certainly reduces the concern of PDF viewer vulnerability that allows local execution access which is the concern here.
bob1029 9mo ago
Does google drive apply any transformation over the PDF, or are you effectively loading the same document in your browser on the round trip?
- Gigachad 9mo ago
  They have some kind of virus scanner for files you open via a share link. Not sure about the ones you have stored on your own drive unshared. But probably the main security here is just using the chrome pdf viewer instead of the adobe one. Which you can do without google drive. The browser PDF viewers ignore all the strange and risky parts of the PDF spec that would likely be exploited.
  - autoexec 9mo ago
    And yet browser PDF viewers still have vulnerabilities and hackers keep finding sandbox escapes.
- venusenvy47 9mo ago
  I often view PDFs in Drive, and it's definitely not just displaying the document with the native web browser. It is rendered with their "Drive renderer", whatever that is. They don't even display a simple .txt file natively in the browser.
- deleted 9mo ago
  [deleted]
creatonez 9mo ago
Firefox has a builtin PDF reader, PDF.js, that resides inside of the Javascript sandbox. In theory, it's as safe as loading a webpage.
- autoexec 9mo ago
  So not actually all that safe since sandbox escapes happen all the time. PDF.js has had many vulnerabilities as well
apyrgiotis 9mo ago
(disclaimer: one of the Dangerzone devs) That's something I do from time to time as well. AFAIK Google Drive renders all documents on the server-side (which implicitly means that they don't trust the browser sandbox), so that's a reasonable price to pay for less privacy. Dealing with sensitive documents though is another story, you just can't upload them to a third-party service. That's where projects like Dangerzone come into play.

gleenn 9mo ago

Do you have any specifics on what Drive does? Any examples of it fixing embedded virii? Or is this blind assumption?

akersten 9mo ago
I assume they mean "upload to drive and use the web based reader to view the PDF," not "upload to drive and download it again"
- gleenn 9mo ago
  And what special sauce does the web preview use? At some point, someone has to actually parse and process the data. I feel like on a tech site like Hacker News, speculating that Google has somehow done a perfect job of preventing malicious PDFs beckons the question: how do you actually do that and prove that it's safe? And is that even possible in perpetuity?
  - deleted 9mo ago
    [deleted]
  - dfajgljsldkjag 9mo ago
    It's an image sent from Google.
  - fc417fc802 9mo ago
    > how do you actually do that and prove that it's safe? Obviously you can't. You assume it's best in class based on various factors including the fact that this is the same juggernaut that runs project zero. They also somehow manage to secure their cloud offering against malicious clients so presumably they can manage to parse a pdf to an image without getting pwned. It would certainly be interesting to know what their internal countermeasures are but I don't know if that's publicized or not.
  - nl 9mo ago
    It certainly reduces the concern of PDF viewer vulnerability that allows local execution access which is the concern here.

bob1029 9mo ago

Does google drive apply any transformation over the PDF, or are you effectively loading the same document in your browser on the round trip?

Gigachad 9mo ago
They have some kind of virus scanner for files you open via a share link. Not sure about the ones you have stored on your own drive unshared. But probably the main security here is just using the chrome pdf viewer instead of the adobe one. Which you can do without google drive. The browser PDF viewers ignore all the strange and risky parts of the PDF spec that would likely be exploited.
- autoexec 9mo ago
  And yet browser PDF viewers still have vulnerabilities and hackers keep finding sandbox escapes.
venusenvy47 9mo ago
I often view PDFs in Drive, and it's definitely not just displaying the document with the native web browser. It is rendered with their "Drive renderer", whatever that is. They don't even display a simple .txt file natively in the browser.
deleted 9mo ago
[deleted]

creatonez 9mo ago

Firefox has a builtin PDF reader, PDF.js, that resides inside of the Javascript sandbox. In theory, it's as safe as loading a webpage.

autoexec 9mo ago
So not actually all that safe since sandbox escapes happen all the time. PDF.js has had many vulnerabilities as well

apyrgiotis 9mo ago

(disclaimer: one of the Dangerzone devs) That's something I do from time to time as well. AFAIK Google Drive renders all documents on the server-side (which implicitly means that they don't trust the browser sandbox), so that's a reasonable price to pay for less privacy. Dealing with sensitive documents though is another story, you just can't upload them to a third-party service. That's where projects like Dangerzone come into play.