pfSense. Been running it on ALIX board for years. Love it.
http://www.pfsense.org/

From the article: "...making it a simple matter for an attacker to decrypt the traffic passing through the device". I'd think it would only be *to* the device.

Yeah. I had not read the exploit. It was apparently a Linux box that was compromised.

Ah. My bad. I just read the exploit summary.

I think this particular instance was more a matter of poor security practices in web development than underlying OS or web server, but it does seem a bit odd that a military branch would use Microsoft/IIS vice using a Unix or Linux platform. It appears that the U.S. Navy is also running IIS for their primary public site.

200 OK
Cache-Control: max-age=334
Connection: close
Date: Mon, 08 Nov 2010 16:56:47 GMT
ETag: "8094fdaf44cc81:287"
Server: Microsoft-IIS/6.0
Content-Location: http://www.navy.mil/usnhome.html
Content-Type: text/html
Last-Modified: Thu, 11 Oct 2007 20:24:13 GMT
Client-Date: Mon, 08 Nov 2010 16:56:48 GMT
Client-Peer: 96.17.8.152:80
Client-Response-Num: 1
Header: US Navy
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eherr@quark:~$ HEAD http://royalnavy.mod.uk/
200 OK
Date: Mon, 08 Nov 2010 15:51:01 GMT
Accept-Ranges: bytes
ETag: "0ee7b62b67dcb1:7904"
Server: Microsoft-IIS/6.0
Content-Length: 70
Content-Location: http://royalnavy.mod.uk/index.html
Content-Type: text/html
Last-Modified: Sat, 06 Nov 2010 13:27:40 GMT
Client-Date: Mon, 08 Nov 2010 15:51:03 GMT
Client-Peer: 94.236.30.11:80
Client-Response-Num: 1
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Debian is vulnerable. I am running Unstable and...

pam_limits is commented out in /etc/pam.d/login and /etc/security/limits.conf has no default user limits:

eherr@chernobyl:~$ ulimit -a
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
file size (blocks, -f) unlimited
max locked memory (kbytes, -l) unlimited
max memory size (kbytes, -m) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 8
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) unlimited
virtual memory (kbytes, -v) unlimited