knockd is a port-knock server. It listens to all traffic on an ethernet interface, looking for special "knock" sequences of port-hits. A client makes these port-hits by sending a TCP (or UDP) packet to a port on the server. This port need not be open -- since knockd listens at the link-layer level, it sees all traffic even if it's destined for a closed port. When the server detects a specific sequence of port-hits, it runs a command defined in its configuration file. This can be used to open up holes in a firewall for quick access.

[ This got memed a while back... I thought it sounded neat, but got my ass handed to me by the actual security nerds on the site, to whom weak security is a worse sin than no security. I shrug. It's a cool idea, if only as a curiosity. -k]

knock - a port-knocking implementation

] Inside Bagle.j, the eighth variant to debut since Friday,
] and which first showed Tuesday, is text taunting Netsky
] that reads "Hey,NetSky, f*** off you b****, don't ruine
] our bussiness, wanna start a war?" (Not exactly
] Shakespeare, and the hacker's spell-checker must not be
] working.)

[ HA! Anyone else think this article is a tad melodramatic calling this a "cyber-war"?

Also, don't talk shit about someone's spelling and then write "back-and-fourth" a couple of paragraphs later... -k]

Security Pipeline | News | Worm Authors Exchange Taunting Messages

] "A visitor to the Adobe Photoshop-for-Windows Forum
] (registration required to post, can log in as guest) has
] described a curious 'feature' with Photoshop 8 (also
] known as 'CS'). Seems this latest version of Adobe's
] flagship product has the built-in ability to detect that
] an image is of American currency. Something has been
] built into Photoshop's core coding that can detect
] something in images of currency and will prevent the user
] from opening the file. Apparently it will also do this
] with Euro notes; info on other currency is pending."

interesting.

Slashdot | Photoshop CS Adds Banknote Image Detection, Blocking?

] Microsoft promised to improve the way in which Windows
] manages computer memory to protect users against commonly
] exploited software flaws known as buffer overruns, which
] can trick Windows into accepting dangerous commands. Some
] of the most damaging attacks in recent months fall under
] this category.

MS deploys non-executable stack patch. (What year is it?)

CNN.com - Microsoft plans Windows overhaul to fight hackers - Oct. 16, 2003

] Crackers obtained the code probably by exploiting a
] vulnerability in Outlook and installing keyloggers,
] according to Valve, the company which develops Half Life.
] Valve's account of the leak is here.

well, much as it sucks for them, companies with millions of dollars of intellectual property should have better security.

Half Life 2 leak means no launch for Christmas

Yeah, yeah! Criminalize security tools! They're only used by h4x0rz anyway!

Nuclear Elephant: Analysis of Symantec's Stance on Censorship