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Showing posts with the label bash

Bash script to email new S3 bucket files as compressed attachments (UDPATED)

I've written a simple bash script that checks for new files in an AWS S3 bucket and emails any that it finds as a compress (tar.gz) attachment  - you can find it at my Github account under the name "S3-Filer-Mailer". I built it as a supplement for a contact form that relies on S3 as a back-end, rather than a php mailer or database. Using S3 for contact forms is attractive because it is so unattractive to spammers. There is no way to corrupt this sort of setup for spamming or to get hands on a database through the form, because it isn't connected to one. Why not use Amazon's Simple Notification Service (SNS) ? For one, AWS charges more for SNS than it does for S3 queries and downloads. For another, if this sort of functionality is available through SNS it is not clearly documented. Getting back to the topic of security, the script establishes two network connections - one a connection to S3 to retrieve the files, the other sending the email. The S3 connection

How To Find Files Over a Certain Size Using Redhat/CentOS/Fedora Linux

Here is a quick tip for all of those Redhat/CentOS/Fedora users out there. Do you need to find all files over a certain size, either in a specific directory, your current directory, or in your entire computer/server? No problem, just execute the following: find / -type f -size +500000k -exec ls -lh {} \; | awk '{ print $9 ": " $5 }' In the example above, I am looking for all files over 500MB in size (500000k, where k = kilobytes). The place where I have typed "/" in the above command indicates the path to search in. By selecting "/" I am searching in the entire filesystem; I could easily indicate a specific directory by changing my command as follows: find /path/to/my/directory -type f -size +500000k -exec ls -lh {} \; | awk '{ print $9 ": " $5 }' Alternatively, I could search in my current directory by replacing "/" with "." like so: find . -type f -size +500000k -exec ls -lh {} \; | awk '{ pri

Patching Your Redhat Server for the Shellshock Vulnerability

Introduction Alright guys, this is a biggie. Shellshock allows remote code execution and file creation for any server relying on bash v3.4 through v1.1. If you are using Redhat or CentOS and the default shell, your server is vulnerable. The patching history was sketchy, as well. If you patched immediately when the bug came out using  CVE-2014-6271 , you are still likely vulnerable (as of right now, 9/26/2013 12:50PM EST). Run the following to apply the patch: #yum update bash You need CVE-2014-7169  if you are using Red Hat Enterprise Linux 5, 6, and 7. Note that 2014-7169 DOES NOT address the following operating systems, which as of right now are still not fully patched: Shift_JIS, Red Hat Enterprise Linux 4 Extended Life Cycle Support, Red Hat Enterprise Linux 5.6 Long Life, Red Hat Enterprise Linux 5.9 Extended Update Support, Red Hat Enterprise Linux 6.2 Advanced Update Support, and Red Hat Enterprise Linux 6.4 Extended Update Support If you applied CVE-2014-6271 and nee