[CentOS] sshd bug?

Matt Keating keatster at gmail.com
Wed Aug 11 15:57:19 UTC 2010


On Wed, Aug 11, 2010 at 4:45 PM, Ray Van Dolson <rayvd at bludgeon.org> wrote:
> On Wed, Aug 11, 2010 at 04:38:22PM +0100, Matt Keating wrote:
>> Hi,
>>
>> I've found a bug/problem with my centos 5.5 server. Any users who have
>> a password of 9 characters or more, only the first 9 characters are
>> used by the OS...
>> eg. i set my password to "123456789" and i try logon via ssh with
>> password "123456789ofgjdfuh" - it lets me in.
>>  and if i set my password to "qwertasdfGHJB" and i enter
>> "qwertasdfSDWQWSDS" - it lets me in...
>>
>> The 'passwd' command only recognises the first 9 characters too...
>>
>> Has anyone seen this before, or know how to fix it? I feel its a major
>> security risk and would like it fixed ASAP.
>
> Sounds like you're using DES password hashes instead of the newer MD5
> style.
>
> If you take a peek at some of the password entries in your /etc/shadow
> do they have a $1$ at the beginning?  If not, you're probably using DES
> which is limited to 8 characters.

Sounds like you're on the money. I didn't install this server, so I
didn't choose the security stuff.
Passwords don't start with $....

> There are a few other places where password length, strength, etc can
> be configured, however I don't recall them off the top of my head.
>
> This is almost certainly not sshd's fault. :)
>
> Ray

Will update shortly....



More information about the CentOS mailing list