Home ›

Paranoid Penguin - Limitations of shc, a Shell Encryption Utility

Issue 138

From Issue #138
October 2005

Aug 26, 2005  By Nalneesh Gaur
 in
The shell script compiler, shc, obfuscates shell scripts with encryption—but the password is in the encrypted file. Could an intruder recover the original script using objdump?
Conclusion

An approach to extract the shell source code successfully from shc version 3.7 generated binary executable was demonstrated. The pub.sh script was used for illustrative purposes only. I have indeed tested the deshc program on executables that I did not create and without access to the source code or the original shell script.

Francisco García, the author of shc, recently released version 3.8. It uses somewhat different data structures and improves upon the security of the previous version. Nevertheless, I believe that embedding the encryption password within the binary executable is dangerous and prone to extraction as discussed in this article.

Nalneesh Gaur, CISSP, ISAAP, works at Diamond Cluster International as a BS7799 Lead Auditor.

______________________

Comments

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

How to work with octave scripts ?

spiriad's picture
Submitted by spiriad (not verified) on Tue, 03/10/2009 - 16:48.

How to make it work with octave scripts, knowing the first line in my_octave_script.sh is #! /usr/bin/octave -q
??

Where we can download DESHC

Anonymous's picture
Submitted by Anonymous (not verified) on Sat, 03/22/2008 - 12:22.

Where we can download DESHC ?

Webcast
More Resources
How to Build an Optimal Hadoop Cluster to Store and Maintain Unlimited Amounts of Data Using Microservers

Realizing the promise of Apache® Hadoop® requires the effective deployment of compute, memory, storage and networking to achieve optimal results. With its flexibility and multitude of options, it is easy to over or under provision the server infrastructure, resulting in poor performance and high TCO. Join us for an in depth, technical discussion with industry experts from leading Hadoop and server companies who will provide insights into the key considerations for designing and deploying an optimal Hadoop cluster.

Learn More

Sponsored by AMD

White Paper
More Resources
Red Hat White Paper: Using an Open Source Framework to Catch the Bad Guy

Built-in forensics, incident response, and security with Red Hat Enterprise Linux 6

Every security policy provides guidance and requirements for ensuring adequate protection of information and data, as well as high-level technical and administrative security requirements for a system in a given environment. Traditionally, providing security for a system focuses on the confidentiality of the information on it. However, protecting the data integrity and system and data availability is just as important. For example, when processing United States intelligence information, there are three attributes that require protection: confidentiality, integrity, and availability.

Learn more about catching the bad guy in this free white paper.

Learn More

Sponsored by DLT Solutions