Last Updated: 2006-08-22 23:35:49 UTC
by Johannes Ullrich (Version: 1)
At this point, we recommend:
- Keep MS06-042 applied if you can. It fixes more bugs than it creates.
- If you are having problems with internal web sites that can no longer be used: Restrict MSIE to be used internally only.
- Use Firefox/Opera or other browsers for now.
- "SandboxIE" can be used to protect your system from damage caused via MSIE.
- If you establish a "No MSIE" policy, you can use the snort rule below to detect accidental policy violations.
alert tcp $HOME_NET any -> $EXTERNAL_NET $HTTP_PORTS \Links:
(content: "|0D 0A|User-Agent\: Mozilla/4.0 (compatible\; MSIE 6.0";)
http://isc.sans.org/diary.php?storyid=1611 (updated patch matrix)
http://research.eeye.com/html/alerts/AL20060822.html (EEye Alert regarding the code execution)
http://blogs.technet.com/msrc/archive/2006/08/16/447023.aspx (MSRC blog article regarding MS06-042 issue, dated Aug. 16th).
http://blogs.technet.com/msrc/archive/2006/08/22/448689.aspx (latest MSRC blog)
Last Updated: 2006-09-11 23:05:04 UTC
by Swa Frantzen (Version: 13)
|#||Known Problems with this patch
||client rating||server rating|
||Botnets actively exploiting this in the WILD
Exploit available in easy to use package
|MS06-041||No reported problems
Original MS06-42: fixes a.o. a FTP vulnerability that;s well-known since 2004
First revision of the MS06-042 patch's buffer overglow has details public.
|MS06-043||No reported problems||Important||Less urgent|
|MS06-044||No reported problems||Critical||Critical|
|MS06-045||No confirmed problems||Critical||Less urgent|
|MS06-046||No reported problems||Critical||Important|
|MS06-047||No reported problems||Trojan dropper reported in word document by Symantec, Trendmicro(1) and Trendmicro(2). The dropper loads a backdoor: Trendmicro, Symantec.
See also diary.
|MS06-048||No reported problems||Trojan dropper in Powerpoint||Critical||Less urgent|
|MS06-049||Unconfirmed reports about corruption of files on compressed volumes.
[Windows 2000 only patch]
|MS06-050||No reported problems||Critical||Important|
|MS06-051||Although unconfirmed by Microsoft so far, there seem to be problems related to Terminal Services and multiple users loading certain DLLs as part of some applications. Details and fixes or workarounds are too sketchy so far.
See also the problem with .ini files and citrix at the citrix support forum.
We're still lookign for a more detailed discription of the problems.
We appreciate updates
US based customers can call Microsoft for free patch related support on 1-866-PCSAFETY
Last Updated: 2006-08-22 15:12:14 UTC
by Johannes Ullrich (Version: 2)
php.ini choices:The following options should be no-brainers and are the default choices for current php installs:
magic_quotes_gpc = OnThe first option will automagically escape all quotes, taking essentially care of 90% of your SQL injection worries. The second part will prevent creative users from adding their own variables without you explicitly requesting them. Extra super secret tip: You probably want to get rid of any php application that breaks after you turn off register_globals.
register_globals = Off
For some extra credit, you can play with 'safe_mode'. But read the instructions carefully. safe_mode is something you best enable before starting to code, as it can be tricky to enable it for an existing application.
/tmp partition:Most php exploits need a bit of space to pull down additional code. Now we don't allow our web server to write files just anywhere. But if you are an exploit, you always got /tmp to use as your "scrap space". Probably the most effective defense against php exploits is to make /tmp its own partition and make it non executable. (and while you are at it, read Swa's tip about mount options). Don't forget to make /usr/tmp and /var/tmp a symlink to /tmp. Any other directory that has to be writable by Apache should be placed on this partition. You don't have to repartition your system. Just use a loopback file.
Honeytokens:The two tips above should protect you from most of the automated codes thats running around the net these days with not too much effort on your side. After all, you need to get back to coding quickly. So how do you keep the more pesky little kids aways from exploring the underbelly of your applications? Now this is where a little bit of IDS and automated response can go a long way. First of all, lets talk dirty for a bit: robots.txt. As the name implies, robots.txt is for 'bots. But then again, some web developers associate magic powers with it and expect it to cloak all files listed in it from all bad influences. Now yes, this may be true. But did you use the key stroke associated with "magic spell" as you edited the file in vi? If not: your files are still all visible and robots.txt can provide a roadmap to an attacker. Consider this robots.txt file pulled from some random website:
Now where would you go today attacking this website?
Simple lesson: Add a good looking file like this to your robots.txt file, with a little twist: "adminpage.php" should not unlock all your secrets. Instead, have it send you a quick e-mail and maybe have the IP added to a shun-list if this page is hit. (Extra credit: Find out how to get yourself locked out of isc.sans.org for the next week... so no playing in the dirt while pretending to wear a white hat).
More Extra Credit:We all love extra credit. So here a couple more pointers:
- chrooting apache/php. Not for everyone, but a very nice extra layer. Quick tip: If you still want to send email from php, look for a program called mini_sendmail.
- mod_security. very nice IDS/IPS style extension for Apache.
- swatch to monitor your log files.
- disable extensions you don't need.
Richard recommends "mod_evasive" as another Apache module to consider:
"In addition to mod_security (which I think is tricky to configure well) I'd recommend mod_evasive. This tool which used to be called mod_dosevasive blocks any IP that makes too many identical requests. For pages that are CPU intensive (which PHP often is) blocking these requests can be a big win.
Sounds like a nice idea.Daniel writes:
"Some other hints:
Also one of the moist exploited PHP functions which should be disable by default: allow_url_fopen."
allow_url_fopen = Off
Of cource, there may be applications that require this feature.