I'n Blog 之萬象真藏

Published: 2008-06-09,
Last Updated: 2008-06-09 22:21:51 UTC
by Scott Fendley (Version: 1)

Last month, it was announced that there was a significant issue involving the Psuedo Random Number Generator (PRNG) on Linux distributions derived from Debian or Ubuntu.  This issue caused the keys used for secure transmissions via SSL or SSH (and other applications) to be very predictable.   If you missed out on these diary entries please see the below URLs.

One of our readers contacted the handler on duty to see if we had seen any reports since then of active attacks concerning this attack vector.  The standard SSH port (22/tcp) has been at normal levels for the past several weeks with one exception (on May 27-28) per the data at Dshield.

The reader pointed us to a blog where it appears there is some activity originating from Debian or Ubuntu based attackers toward various servers.  Looking at the limited bit of information in the blog, I think it is most likely just run of the mill brute force attacks which coincidentally originated from these particular Linux distros.  In my particular area, I have seen a drop in SSH based attacks and an increase of targeted phishing scams in the past month.

Seeing that there isn't a major uptick in the past week or so, I would supposed that the attackers are taking a slower and less noisy approach on attacking the SSH vector.  In any case, we are still interested in packet captures should any of you see any attacks which seems out of the ordinary.

References:

http://isc.sans.org/diary.html?date=2008-05-15

http://isc.sans.org/diary.html?storyid=4414

資料來源  http://isc.sans.org/