News Report on Non Vulnerability in Windows Vista

November 20th, 2008 by Chris Wysopal

Are editors so excited to use the headline “Vulnerability in Windows Vista” in their SEO URLs that they will have their reporters write a story on a non-issue?

IDG News has published a news report titled, “Researchers find vulnerability in Windows Vista“. The report says:

An Austrian security vendor has found a vulnerability in Windows Vista that it says could possibly allow an attacker to run unauthorized code on a PC.

The problem is rooted in the Device IO Control, which handles internal device communication. Researchers at Phion have found two different ways to cause a buffer overflow that could corrupt the memory of the operating system’s kernel.

In one of the scenarios, a person would already have to have administrative rights to the PC. In general, vulnerabilities that require that level of access somewhat undermine the risk since the attacker already has permission to use to the PC.

Somewhat undermine the risk? If you need admin rights to exercise a bug it is not a security issue since you could already run any code with whatever privilege you wanted. Microsoft is not issuing a patch, but creating a bug fix in a service pack, yet this is newsworthy? This story has no comment from anyone but the finder of the bug. Let’s see if other news outlets pick up on this one.

À tout seigneur, tout honneur…

November 16th, 2008 by Sid

Credit for Researchers

November 13th, 2008 by Chris Wysopal

Computer security researchers are much like scientific researchers in several ways. We build on the research of those who come before us, we sometimes rediscover the same things independently, and other times we forget where we learned things and sometimes claim them as our own. We also occasionally take an engineer’s approach and implement research discovered by others and not credit them as it’s the implementation into a tool that matters to us.

The latest Microsoft patch MS08-68 is a great example. It is a problem with NTLM authentication where the attacker can force a client to authenticate to him and the credentials, while not exposed in cleartext, can be relayed to another server or brute forced to obtain the cleartext. This is a very classic crypto protocol vulnerability. It’s not the crypto algorithms that are the problem, but the protocol implementation.

Microsoft recently fixed the problem, perhaps due to the availability of exploit code, the availability of an easy to use Metasploit implementation, or perhaps Microsoft’s changed tolerance for vulnerabilities. We can sum it up as a change in the threat space that made it worth fixing. But make no mistake, this is a very old problem.

News reports have been citing Sir Dystic’s SMBrelay tool, which was published in March, 2001, as the first knowledge of this vulnerability. Eric Shultze who worked at MSRC in 2001 just yesterday is quoted as saying, “I have been holding my breath since 2001 for this patch.” Obviously it is a long time coming. But this wasn’t the first publication of the problem. In 2000, one of my collegues on the research team at @stake, Christien Rioux (aka Dildog) published the telnet NTLM authentication vulnerability.

Rioux’s advisory has a great description of the credential relay and cracking weaknesses. I have talked to him and he says he discovered these problems independently, but he didn’t find them first. Dominique Brezinski published exactly these NTLM vulnerabilities in the SMB protocol in 1996 in a paper titled, “A Weakness in CIFS Authentication”. The earliest reference I can find on the paper on the net is here where it is included in another paper published in 1997. Such is the ad-hoc world of independent security research of 12 years ago which still continues today.

It seems ridiculous that a field like security research, which is so important to the running of modern society is so ad-hoc. Shouldn’t we know who discovered a vulnerability? Shouldn’t all researchers and engineers know about it? More importantly if someone implements a tool that takes advantage of a vulnerability shouldn’t they credit the discoverer? Don’t get me wrong. Implementation takes a lot of work and sometimes makes all the difference in makeing people aware of a security problem. After all when I was at the L0pht our slogan was, “Making the theoretical, practical”. I still think researchers should get credit when credit is due.

The security community has gotten better at documentating our research but I still see instances of independent discovery, misplaced credit, and tools giving no credit to researchers. I hate to say it but getting a bit more academic is in order. Credit is the currency of a researcher and placing it well will reward the right people and we will all benefit.

Microsoft Fixes 8-year Old Design Flaw in SMB

November 12th, 2008 by Christien Rioux

With regard to the recent Patch Tuesday fix, there has been an issue fixed regarding NTLM Relaying, that has been around for more than eight years.

In 2000, I wrote an advisory about NTLM relaying (CVE-2000-0834). The problem turned out to be significantly larger than I originally suggested in the advisory. The attack extended to other NTLM-based authentications on other protocols and allowed general-purpose credential theft via a man-in-the-middle attack.

The SMBRelay tool was published in 2001 by Sir Dystic of Cult Of The Dead Cow, and that really took it to the next level. The protocol completely fell apart. It kicked off a number of other analyses of the NTLM protocol that finally resulted in this patch. Eight years after it’s discovery.

At least they got around to it. Thanks!

Des fameuses faiblesses de TKIP…

November 9th, 2008 by Sid

links for 2008-11-07

November 7th, 2008 by Raffael Marty

Now that the presidential race is over Newsweek is reporting that the US Government, through the FBI and Secret Service, notified the Obama and McCain campaigns that their computers had been compromised and sensitive documents copied.

…the FBI and the Secret Service came to the campaign with an ominous warning: “You have a problem way bigger than what you understand,” an agent told Obama’s team. “You have been compromised, and a serious amount of files have been loaded off your system.” The following day, Obama campaign chief David Plouffe heard from White House chief of staff Josh Bolten, to the same effect: “You have a real problem … and you have to deal with it.” The Feds told Obama’s aides in late August that the McCain campaign’s computer system had been similarly compromised.

This information demonstrates that the US government has a sophisticated intrusion detection capability. This is likely part of the NSA internet surveillance system that was made public by an AT&T technician in 2006.

It is likely that the system has a set of watch IP ranges that are sensitive from a national security perspective. The campaigns’ computers were probably on this list. The traffic between foreign IP addresses and these watch IPs is then scrutinized for espionage. The pattern of activity flagged would be Microsoft Office documents and PDFs being retrieved or other intruder signs such as an encrypted tunnel with a foreign endpoint.

This shows that the US Government has the capability to detect some types foreign attacks although they probably have to be selective of the IP ranges they monitor. It’s nice to know that if the White House computers were leaking documents to China or Russia that there is some detection capability, but the fact that this is done at the Internet backbone level means any IP could be targeted and it might not just be to look for foreign intrusions.

TKIP, comment ça marche ?

November 7th, 2008 by Sid

Picviz: Let’s see uncommon URL (part 2/?)

November 6th, 2008 by toady

Today, I would like to see if the urls that are not common in the previous graph, In this graph, heatline rendering plugin is used to check with line coloration if an event is regular. In the fourth axis, you can see lines going at the bottom and red lines go there. So let's forget about this and filter to only display lines that appear above 50% of this axis.

The filter is between single quotes, just like what you'd do with tcpdump ( I actually took their code to handle this ;-) ).

This line was typed to get the graph you can see here:
pcv -Tpngcairo -Rheatline -Avirus access-wallinfire.net.pcv 'show plot > 50% on axis 4' -ra > picviz-uncommonurls.png

If we take a random IP, such as the one we clearly see on the second axis, 213.192.60.19, and googling about it, we find that this was an infected machine. The url here tells more about it.

As a conclusion for this graph, you can see that among all those lines of log, with a very empiric approach, we really discovered something. Not a very innovative attack I admit, but enough to keep searching (I will post ongoing researches here, keep following!).

Ah, and by the way Raffy, since you asked to only display lines every few times, I added the -L option, taking a number (N) as argument meaning every N lines you display the text.

Picviz graphing apache logs

November 5th, 2008 by toady

This parallel coordinates graph shows 412429 lines of one of my wallinfire.net access log with generated with Picviz svn. This is the first of a set of graphs which will derivate from this one. The most complete one.

To generate such a graph, simply use the apache-access2picviz Perl script available from trunk/tools. Then, use the heatline plugin to see line frequencies: the more green the line is, the lowest it appears. When a line is in red, it means it comes often. This way you can easily see if an event is regular or not. To generate this image, you can type: pcv -Tpngcairo access.pcv -Rheatline -Avirus -rra > accesslogs.png

First axis = Time (24 hour) with 00:00 at the bottom and 23:59 on the very top.

Second axis = Source IP with 0.0.0.0 at the bottom and 255.255.255.255 on the very top.

Third axis = HTTP request type.

Fourth = Request

Tomorrow, I will post a filtered graph, on the request axis to see what are the IP addresses that are doing abnormal requests.

Picviz is available as free software on http://www.wallinfire.net/picviz