LinuxQuestions.org
Help answer threads with 0 replies.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Security
User Name
Password
Linux - Security This forum is for all security related questions.
Questions, tips, system compromises, firewalls, etc. are all included here.

Notices


Reply
  Search this Thread
Old 09-30-2014, 06:47 PM   #1
Highjo
Member
 
Registered: Jan 2007
Posts: 36

Rep: Reputation: 0
SSL: disable RC4 ,CBC and weak ciphers


Hello Security Expert.

I am running an application in apache using mod_ssl. A quick scan has revealed that the server supports CBC ciphers , RC4 for TLSv1, RC4 for SSLv3, weak MAC for SSLv3 and weak MAC for TLSv1.

My first approach after lots of google search is to this is to do the following:

Quote:
SSLProtocol -ALL +SSLv3 +TLSv1
CipherSuite ALL:!ADH:!RC4:+HIGH:+MEDIUM:!LOW:!SSLv2:!SSLv3!EXPORT
I am not really sure whether this is in the right direction. I need some advice please. Thanks in advance
 
Old 10-01-2014, 03:30 PM   #2
unSpawn
Moderator
 
Registered: May 2001
Posts: 29,415
Blog Entries: 55

Rep: Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600Reputation: 3600
See http://httpd.apache.org/docs/2.0/mod...oxyciphersuite or https://www.sslshopper.com/article-h...in-apache.html and then test it.
 
Old 10-01-2014, 07:35 PM   #3
sundialsvcs
LQ Guru
 
Registered: Feb 2004
Location: SE Tennessee, USA
Distribution: Gentoo, LFS
Posts: 10,659
Blog Entries: 4

Rep: Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940Reputation: 3940
Also please note ...

In most cases, "penetration of a cipher system" rarely-if-ever occurs due to the theoretical "weakness" of the cipher system. Instead, it occurs due to "other factors." Such as ... a pistol being pointed at the young daughter of the father who possesses the key, or ... a functional weakness in the key management/negotiation system.

The SSL protocol, like all other such modern cipher systems, employs public-key infrastructure (PKI) to negotiate a "one-time, random, session key" that is subsequently used in a conventional ("asymmetric") encryption algorithm. Also by design, it enables the two parties to negotiate which particular algorithm will be used.

So, "the algorithm, whatever-it-is," and "the key, whatever-it-is," will only be used once, for this particular exchange, which is of a finite length. (The protocol also provides for periodic re-negotiation, if necessary.) Therefore, even a "theoretically 'weak(er)'" algorithm is likely to be pragmatically sufficient, because it is being used in a strong way.
 
Old 10-04-2014, 11:48 AM   #4
Highjo
Member
 
Registered: Jan 2007
Posts: 36

Original Poster
Rep: Reputation: 0
Hello All,

Thanks for your answer. I will test and revert
 
  


Reply

Tags
security, ssl, vulnerability



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Need help disabling weak SSL ciphers for PCI scan neodaemon Linux - Server 1 10-17-2013 02:45 AM
Apache disable SSL on a virtual host cashton2k Linux - Server 2 01-22-2010 04:17 AM
Disable SSL v2 in Apache cooljai Linux - Server 3 10-15-2009 11:31 AM
Nessus scan reveils weak ciphers neocontrol Linux - Security 1 03-18-2008 05:26 PM
weak ssl ciphers in webmin hari_seldon99 Linux - Security 2 12-04-2004 06:33 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Security

All times are GMT -5. The time now is 12:43 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration