nbpoole
Joined 16 years ago
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Recent submissions
Comment · 11 years ago
As far as I'm aware this is the first time I've been mentioned in a conspiracy theory. So thanks for that. :-)
Comment · 13 years ago
Interesting: this sounds like a recurrence of the same issue which was described a number of months back:
https://www.digitalocean.com/blog_posts/resolved-lvm-data-is...
At the time, the blog post claimed that the issue was resolved and that data was now being wiped by default. I wonder why that would have changed.
Comment · 13 years ago
I think tptacek's point is that the answer to your question is spelled out very clearly on the page. ;-)
From the page:
> You should own Ferguson and Schneier’s follow-up, Cryptography Engineering (C.E.). Written partly in penance, the new book deftly handles material the older book stumbles over. C.E. wants to teach you the right way to work with cryptography without wasting time on GOST and El Gamal.
Plus a whole section at the end which starts with "If this stuff is interesting to you, here’s some additional reading:"
Comment · 13 years ago
If that were true it would be a major security vulnerability. ;-)
The Google Translate content is served up from a subdomain of googleusercontent.com. This is a domain designated by Google for user-supplied content so that it can be rendered without affecting the safety of pages on google.com and elsewhere.
The demonstration here is that one page on googleusercontent.com can affect another page on googleusercontent.com. This is perfectly acceptable via the same origin policy.
Comment · 13 years ago
This was posted yesterday: https://news.ycombinator.com/item?id=6080048
Comment · 13 years ago
Right. But your post shows that you can reliably get the browser to crash. It doesn't demonstrate that the crash is exploitable, unless I'm missing something.
Comment · 13 years ago
Right. But I can very easily find reports of reliable ways to crash IE via CSS: https://www.google.com/search?q=crash+ie+css
I don't have a problem with your blog post. It documents how to reproduce the issue referenced in a particular CVE. But I'm curious what value people are deriving from reading it.
Comment · 13 years ago
Not sure why this is getting voted up so much. The author came across a report of IE freezing/crashing, replicated it, and Microsoft fixed it. In the same security update (http://technet.microsoft.com/en-us/security/bulletin/ms13-03...) there are 10 other vulnerabilities described in the same way. Why is this particular vulnerability noteworthy or interesting, other than the fact that someone stumbled across it and documented it before it ended up reported to Microsoft?
In fact, CVE-2013-1297 from that same security update (which I didn't know existed until now) is far more interesting from a security perspective (http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2013-1...).
Microsoft Internet Explorer 6 through 8 does not properly restrict data access by VBScript, which allows remote attackers to perform cross-domain reading of JSON files via a crafted web site, aka "JSON Array Information Disclosure Vulnerability."
Similar JSON information disclosure can be very serious for a web application. http://haacked.com/archive/2009/06/24/json-hijacking.aspx describes the general issue in some depth. The fact that it was possible to use vbscript as a way to read in cross-domain JavaScript is very important from a security perspective.
Comment · 13 years ago
Luckily, this question has been asked and answered fairly recently!
Specifically https://news.ycombinator.com/item?id=5955043 from last week, complete with a response from Matt Cutts (https://news.ycombinator.com/item?id=5955374):
> It's not that PG has a grudge against Google (or vice versa) or anything like that. I believe that search engine bots crawl Hacker News hard enough that PG blocks most crawling by bots. In the case of Google, he does allow us to crawl from some IP addresses, but it's true that Google isn't able to crawl/index every page on Hacker News.
> Here's a link where I answered the same question about three weeks ago: https://news.ycombinator.com/item?id=5837004 , so this isn't a new issue. In fact, PG has been blocking various bots since 2011 or so; https://news.ycombinator.com/item?id=3277661 is one of the original discussions about this.
> And to show this isn't a Google-specific issue, note that Bing's #1 result for the search [hacker news] is a completely different site, thehackernews.com: http://www.bing.com/search?q=hacker+news
> In general, I think PG's priority is to have a useful, interesting site for hackers. That takes precedence and is the reason why I believe PG blocks most bots: so that crawling doesn't overload the site.
Comment · 13 years ago
I believe that's how Rails works, except using an HMAC on the cookie instead of AES (since AES itself doesn't prevent tampering).
Comment · 13 years ago
You can't just read cookies for arbitrary domains in an iframe.
Comment · 13 years ago
Not in general, no. You can drop replay protection as a requirement and that gets you to actual statelessness. If you then have your website on a single domain and never put anything else onto other subdomains, theoretically now the only risk is that your single application is vulnerable to XSS. But you shouldn't build your security based on assumptions like that if you can help it.
Comment · 13 years ago
"Stateless" CSRF protection as described here is strictly inferior to other forms of protection. The reasons are somewhat laid out in this blog post's comments:
1. JavaScript in any subdomain allows a cookie to be set on unrelated subdomains. That means an attacker can set a token and override the CSRF protection entirely.
2. The "replay protection" means that you must continue to maintain state on the server (ostensibly to prevent duplicate requests)
The author has actually gone on to propose a "triple submit" system for CSRF protection (http://www.slideshare.net/johnwilander/stateless-anticsrf) which is still vulnerable to compromise if a related subdomain can be used to attack by setting many cookies.
For a more thorough discussion of CSRF mitigations, check out https://www.owasp.org/index.php/Cross-Site_Request_Forgery_(...
Comment · 13 years ago
"This wouldn't happen if Yahoo had a Vulnerability Reward Program"
As much as I support these kinds of programs (https://nealpoole.com/blog/responsible-disclosure-programs/), that's a false dichotomy. Some companies have responsible disclosure policies or vulnerability reward programs. Some companies don't.
Anecdotally, the companies that do have programs don't inherently respond more quickly or handle reports better (ie: https://nealpoole.com/blog/2013/04/experiences-with-the-yand..., https://nealpoole.com/blog/2013/03/csrf-persistent-xss-in-my...). In contrast, companies that don't have programs may still be very responsive and willing to work with researchers; I reported issues to GitHub, Etsy, and Facebook before their respective programs were in place and they always responded quickly and effectively.
It comes down to the people who focus on security at the company and the way in which security is prioritized. If your company doesn't value and prioritize security, a responsible disclosure program won't make anyone's life easier.
In that sense, I do think that companies can and should do a better job of working with security researchers, regardless of whether they have a responsible disclosure program or vulnerability reward program in place. If a company takes security seriously, it should make it easy for researchers to report vulnerabilities. Researchers shouldn't feel that their reports are being sent into a black hole: if they do, they'll be less likely to spend their time reporting issues in the future.
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