Threat Level: green Handler on Duty: Daniel Wesemann

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Obvious Lessons from the Skype outage

Published: 2010-12-30
Last Updated: 2010-12-30 20:17:27 UTC
by Rick Wanner (Version: 1)
2 comment(s)

Abel Avram has posted an interesting analysis of the causes and solutions of the December 22nd Skype outage that affected millions of users.

In short the outage was caused by a bug in the undelivered message code.  This bug had been fixed in a subsequent version, but 50% of Skype users were still using the buggy version.  With Skype being a peer-to-peer application, and 40% of Skype clients crashing when the undelivered messages attempted delivery, it caused undo strain on the remaining Skype users' machines.  These clients then left the Skype network to protect themselves; thus causing a cascading network failure.

Most interesting are the lessons, which in retrospect seem a little obvious:

  • "One important lesson to be learned is this: many users do not update their software if they don’t have to...".   Apparently Skype is considering a Google Chrome style invisible update.
  • "Skype deciding to review their “testing processes to determine better ways of detecting and avoiding bugs which could affect the system.”"
  • “will keep under constant review the capacity of our core systems that support the Skype user base, and continue to invest in both capacity and resilience of these systems.”

Patching, testing; and adequate capacity.  Aren't these pretty much the cornerstones of effective IT?

-- Rick Wanner - rwanner at isc dot sans dot org - http://namedeplume.blogspot.com/ - Twitter:namedeplume (Protected)

Keywords: outage Skype
2 comment(s)

SamuraiWTF Review over at ISSA Toolsmith

Published: 2010-12-30
Last Updated: 2010-12-30 03:53:47 UTC
by Rick Wanner (Version: 1)
0 comment(s)

One place I try to keep up with is Russ McRee's ISSA Toolsmith reviews of security tools.  The December edition of the Toolsmith contains Russ's review of SamuraiWTF. SamuraiWTF is web-application pentesting framework on a liveCD assembled by Justin Searle from InGuardians and fellow ISC Handler Kevin Johnson of Secure Ideas. 

Although SamuraiWTF is really too big to review in one magazine article, Russ does hit the high points in his review and concludes that "SamuraiWTF rocks, plain and simple".  It seems clear that if you spend any time doing webapp pentesting this is a tool that you should take a closer look at.

 

-- Rick Wanner - rwanner at isc dot sans dot org - http://namedeplume.blogspot.com/ - Twitter:namedeplume (Protected)

0 comment(s)
Critcal Wordpress Security Update http://wordpress.org/news/2010/12/3-0-4-update/
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