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Re:Stealing private documents through a bug in Google Docs by xyst on Monday December 28, 2020 @09:13AM (#25559272)
This was a bug that affected multiple products and even crossed into the enterprise suite and google only rewarded $3.3K USD?

It’s almost as bad as Apple’s reward program

Re:Stealing private documents through a bug in Google Docs by jfindley on Monday December 28, 2020 @01:23PM (#25561597)
It's definitely a vulnerability, but to be a little more grounded in reality, to exploit this you need to somehow convince your victim to go to your website which contains the document you're trying to get access to.

So for this to work you need to know the document ID, and also the person who owns this document. You then need to trick them into looking at their document on your domain, and then from there, need to persuade them somehow to press the send feedback button.

I'd also note that the feedback button is a button that I suspect very very few people ever press. I certainly never have. I also don't know the IDs to any documents I might find interesting but can't read, and if I find a document via some random google search that I can't look at, I generally have no way of knowing how to contact the owner so I can try to send them phishing emails to get them to look at their document on a non-google URL.

There's been a bunch of cases where google has paid out very substantial bounties, and given the extreme difficulty of both meeting the attack prereqs and then managing to pull off a very sketchy exploit process at the same time I think the sum paid is more than fair.

Re:Stealing private documents through a bug in Google Docs by tptacek on Monday December 28, 2020 @02:28PM (#25562344)
Oh, I didn't even think about this, but I think you're right: there's no generic way of iframing a victim where you can see all their document IDs. This doesn't seem very plausible.
Re:Stealing private documents through a bug in Google Docs by gibba999 on Tuesday December 29, 2020 @05:19AM (#25568459)
I'm on cc: lists with documents I don't have access to all the time. It depends on how organizations interact. And I suspect it wouldn't be very hard for me to iframe Google Docs and appropriately obscure things so someone does, indeed, click where I want.

$3.3k is about a week's worth of time for a poorly-paid developer before overhead.

It's not reasonable. At those rates, the only people who will be able to afford to be paid to do security work on Google products will be ones who sell on the gray/black market. The whole point of bounties was to give a path without the need for that.

Re:Stealing private documents through a bug in Google Docs by treeman79 on Monday December 28, 2020 @01:43PM (#25561865)
Way easier to convince customer to share the document.
Re:Stealing private documents through a bug in Google Docs by foolmeonce on Monday December 28, 2020 @05:13PM (#25563872)
True, but I think a business account can disable the simple "share" to outside accounts and there would be more logs (of the type the business would be able to see) of what happened.

These exploits are often not so interesting as written and with current normal setups, but eventually become more interesting if never fixed.

Re:Stealing private documents through a bug in Google Docs by tptacek on Monday December 28, 2020 @06:55PM (#25564848)
Can you lay out a realistic exploitation scenario for this bug? It seems to have several predicates:

1. You need to know the document ID you're targeting (Stack Exchange once worked the ID out to ~256 bits).

2. You have to get the victim to interact with a Google doc on a site that you control (you need to re-dress the Google Docs interface, get the victim to your site, and then have them treat your site as if it was Google Docs).

3. You need to get the victim to use the Google feedback feature in order to trigger the vulnerable postMessage.

What's a scenario in which an attacker gets these stars to align? (I'm sure there is one).

Re:Stealing private documents through a bug in Google Docs by foolmeonce on Tuesday December 29, 2020 @03:05AM (#25567744)
Sure, why not:

1. I go to a job interview at a company that uses a chromebook with a restricted account. The interviewer sits next to me as I go through the process.

2. As we go through the steps in a google document, I need something from my resume on my website. I fumble with the URL bar slightly which hopefully has the doc ID, possibly because I once closed the document "by accident" and brought it back up.

3. While discussing whatever brought us to my website, I click on something but act like I am switching tabs.

4. At the end of the process in their document, I point out how strange the Google Docs looks now and press the feedback button to show my corporate soft skills.

5. The companies hiring interview document is now floating around my school and in 10 years half of their engineering is my Alma Mater.

Re:Stealing private documents through a bug in Google Docs by pvg on Tuesday December 29, 2020 @08:24AM (#25569519)
At that level of realism there are much more efficient attacks

https://i.imgur.com/lkUV5Mf.jpg

Re:Stealing private documents through a bug in Google Docs by refulgentis on Tuesday December 29, 2020 @03:35AM (#25567887)
This is implausible as well, no one simply 'goes to a company', offices are long gone.
Re:Stealing private documents through a bug in Google Docs by tptacek on Monday December 28, 2020 @01:11PM (#25561471)
Isn't this essentially a Clickjacking bug? Doesn't the victim have to (1) deliberately have a sensitive document open, (2) be somehow framed by an attacker's malicious IFrame, and then (3) click the "submit feedback" button to report a problem to Google?

All three of those conditions are independently rare. The equivalent conditions are rare in all CJ bugs, which is a reason CJs are sort of a running joke in appsec. This bug isn't a joke (look at the target and the impact), but condition (3) is also way more unlikely than the median CJ report somewhere else.

If I understand the bug correctly --- maybe I don't --- this researcher got what might perhaps be the largest bounty ever paid for a CJ bug.

Re:Stealing private documents through a bug in Google Docs by Thorrez on Monday December 28, 2020 @09:03PM (#25565847)
This seems a bit different than clickjacking to me. In CJ, the victim performs sensitive actions because the UI is obscured. Here the UI is unobscured, and the user performs actions that should be fairly unsensitive.
Re:Stealing private documents through a bug in Google Docs by kyrra on Monday December 28, 2020 @09:51AM (#25559580)
(Googler, opinions on my own)

Are you sure this impacted multiple products? Reading the article the main reason he was able to exploit this for Google docs was the X-Frame-Options header. It's not clear that other products have this.

Re:Stealing private documents through a bug in Google Docs by sit_i_piz on Monday December 28, 2020 @09:54AM (#25559605)
It works on other Google product that has the "Submit Feedback" link on it. I just tested this out with Google Webmasters and it's an issue there as well.
Re:Stealing private documents through a bug in Google Docs by Jabbles on Monday December 28, 2020 @10:00AM (#25559652)
It is unlikely they wouldn't have checked other products as part of the fix. So I'm going to ask for more proof that you "tested this out".
[dead]
Re:Stealing private documents through a bug in Google Docs by tptacek on Monday December 28, 2020 @01:24PM (#25561612)
You can't comment like this on HN; accusing other commenters of having secret conflicts of interest is the HN Guideline 'dang corrects most often here:

https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...

Re:Stealing private documents through a bug in Google Docs by jtbayly on Monday December 28, 2020 @03:47PM (#25563043)
Doesn’t seem like an accusation of a conflict of interest to me. Just pointing out who has the burden to test. Since one is paid by the company, it does make sense for testing the company’s products would be his responsibility first.

Whereas the previous comment was accusing the other one of lying about testing it.

Re:Stealing private documents through a bug in Google Docs by tptacek on Monday December 28, 2020 @04:01PM (#25563164)
Did I miss the place on this thread where the person we're talking about said they worked for Google?
Re:Stealing private documents through a bug in Google Docs by jtbayly on Monday December 28, 2020 @05:46PM (#25564169)
Nope. Sorry. I messed up. Thought I saw the same person commenting who he already said they worked at Google.
Re:Stealing private documents through a bug in Google Docs by alisonkisk on Monday December 28, 2020 @04:19PM (#25563345)
An employee of X is better suited to investigate a bug in X than a non-employee is
Re:Stealing private documents through a bug in Google Docs by gruez on Monday December 28, 2020 @09:37AM (#25559467)
>It’s almost as bad as Apple’s reward program

Or most/all bug bounty programs, actually.

Re:Stealing private documents through a bug in Google Docs by julianlam on Monday December 28, 2020 @01:32PM (#25561721)
I hear this refrain often, and it is of course never followed up with a solution.

What would you suggest, a bounty calculated via a multiple of company stock price?

Re:Stealing private documents through a bug in Google Docs by throwaway2048 on Monday December 28, 2020 @02:14PM (#25562189)
I think its pretty obvious the solution to "not paid enough money" is "pay more money"
Re:Stealing private documents through a bug in Google Docs by rtx on Monday December 28, 2020 @02:59PM (#25562613)
How should the price be discovered.
Re:Stealing private documents through a bug in Google Docs by kreeben on Monday December 28, 2020 @05:52PM (#25564233)
while (recipient_is_unhappy_with_amount) { amount *= 3.14; }
Re:Stealing private documents through a bug in Google Docs by vermilingua on Monday December 28, 2020 @07:28PM (#25565095)
That’s an effective way for recipients to always be “unhappy” with the bounty.
Re:Stealing private documents through a bug in Google Docs by Razengan on Monday December 28, 2020 @08:28PM (#25565584)
How should their happiness be ascertained? Their word?
Re:Stealing private documents through a bug in Google Docs by ancarda on Monday December 28, 2020 @03:05PM (#25562656)
Offer them a job.
Re:Stealing private documents through a bug in Google Docs by TedDoesntTalk on Monday December 28, 2020 @03:30PM (#25562878)
If you don’t like how much they pay, maybe don’t brand yourself a “security researcher” and then try to earn the equivalent of full-time pay by finding bugs in other peoples products and blogging about it?
Re:Stealing private documents through a bug in Google Docs by swypych on Monday December 28, 2020 @12:18PM (#25560967)
This provides very little incentive for future good actors to search for these exploits... I had no idea the reward would be so low.
Re:Stealing private documents through a bug in Google Docs by fractionalhare on Monday December 28, 2020 @11:00PM (#25566581)
> This was a bug that affected multiple products and even crossed into the enterprise suite and google only rewarded $3.3K USD?

They could have also offered nothing, which was common up until a decade ago or so. Moreover there isn't a market for security bugs like this, so it's not like Google is underpaying relative to some independent valuation.

The only reason to pay more is out of some ethos that the reporter "deserves" more, but that's not how business works. The value Google obtains by finding any given vulnerability approaches 0. This is why, among other reasons, good product security teams spend most of their time doing things other than searching for vulnerabilities in existing code.

Re:Stealing private documents through a bug in Google Docs by meibo on Monday December 28, 2020 @01:13PM (#25561489)
You do need to actually "give feedback" to trigger this, which seems a bit far off for a corporate worker - might be why they didn't think this was high impact, of course it should have been higher though.
Re:Stealing private documents through a bug in Google Docs by IncRnd on Monday December 28, 2020 @06:25PM (#25564563)
The level of reward is related to the exploitability and attack vector not just the results of being exploited.