Tag: bash

  • `Shellshock` Bash Patch update – pipe directly to sh to secure your machine

    Recently, I made the script to patch your BASH environment available on this site, but that meant a need to copy and paste.

    Using a user with the appropriate rights, you can now pipe directly using a quiet wget to make the full recompile to most recent BASH version possible.

    All you need is this line: (more…)

  • `Shellshock` bash vulnerability fix and update in case of slow or unavailable repositories

    Updated to latest kernel patch bash43-30

    You’ve heard of ShellShock, and the bash-exploits that are currently doing the rounds, across platforms, that make use of these bugs (CVE-2014-6271 and the volumes of additional updates including CVE-2014-6277, CVE-2014-7186, CVE-2014-7187 and CVE-2014-7169, but to name a few). Proofs of Concept are being collected here… The below works as a vulnerability fix for older Ubuntu LTS and non-LTS versions, Debian (eg Squeeze) as well as Fedora and RedHat/CentOS, and applies all up-to-date patches to Bash.

    bash – as a shell – is a tried and trusted component. Some legacy systems’ repositories – be they apt, yum or other – may no longer be kept up to date. Alternatively, they may not be being kept up-to-date enough for your liking. And you want to close the bash issue in the best way you know how.

    Easy workaround is a recompile of the bash shell yourself:

    (more…)

  • How to block or drop attacker with null route

    Quick note to myself, as I keep forgetting the syntax, though it is so easy — to block an incoming connection by null routing or rejecting the connection is as simple as

    route add -host IP reject

    To apply this to a whole subnet range, use the -net as you would with the /24 mask (or the appropriate subnet, /29 or smaller should do), eg

    route add -net IP/RANGE reject

    To undo this,

    route delete IP
  • Search and view gzip’d files

    You knew it already – but I keep forgetting – the power of zgrep and zcat both of which behave as their z-less counterparts.

    So, to search a gzip’d file, you can simply zgrep <term> <filename.gz>, or to cat/view it, zcat <filename.gz>

    Good to come back to in case of impending forgetfulness…

  • Search all files for TEXT in bash

    To find all files by file name containing THE TEXT I SEEK:

    grep -lir "THE TEXT I SEEK" *

    (more…)

  • On the fly compression of a tar-ball or mysqldump

    Just to jot it down lest I forget:

    Tar’ing the local directory and streaming the tarball straight to gzip:

    tar cvf - . | gzip > target.tar.gz

    MySQLdump’ing directly to gzip: (more…)

  • Secure SSH Tunneling – at no extra cost

    Assuming you have a Windows machine and you interact with Linux boxen at any stage, chances are high that you have used and interacted with PuTTY at one stage or another. That beautiful, less than 2 sec, 444K download of a tool (currently at version 0.60 beta) allows you to SSH, COM-direct, RSH, Telnet etc from the desktop. Both examples below relate to MySQL port tunneling.

    SSH Tunnels using the Bash command line

    Running on a proper machine (or even a Windows with Cygwin or a Mac Terminal) allows you to quickly tunnel a session to a remote server: (more…)

  • Install Webmin on Ubuntu

    Just a quick note (as I keep forgetting, and a cut-and-paste solution is a quicker time to market) – but you knew that already. Installing Webmin is quite simple (download directly, or from the mirrors). Currently, 1.510-2 is the latest version – check on www.webmin.com for further details. As an aside, the book Webmin Kompakt – by Holger Reibold – is available for download!

    So here’s a simple step-by-step: (more…)

  • Testing POP3 and IMAP servers from the command line in CMD or bash

    It’s quite simple, really: POP3 (Exchange, dovecot etc) you know, IMAP (Exchange, dovecot, courier etc) you know — so this is just a recap, right? You know how to telnet into the machine — in Vista or Windows 7, you may need to install it separately using “Add/Remove Programs”, or just use Putty in Telnet mode…  otherwise, apt-get install telnet if it’s not on your machine (or yum install telnet)

    POP3:

    telnet SERVER 110 (more…)

  • Wipe all mp3s and avis from the filesystem

    So you want to run a script that removes all mp3 and avi files off the filesystem. One way (in bash) as below. Comment, suggestions and feedback are welcome 🙂 Using $EUID to check for root user, and $IFS to check for line breaks as the file names has spaces in them. IFS is saved to a temp variable, reset and then re-instated afterwards. C is the counter. Got two litte for loops in bash with backtick execution.

    (more…)