Re: Compromised Passwords

2014-04-04 Thread Rob Tanner
On Mar 4, 2014, at 7:25 PM, Venkat mvenkat...@gmail.commailto:mvenkat...@gmail.com wrote: When a password gets compromised, spam starts to pour out of the server from endless numbers of IP's, to endless numbers of addresses. Rate limiting is interesting but doesn't really stop the spam.

Re: Compromised Passwords

2014-03-06 Thread Adam Moffett
Homer: Two steps eliminated this problem for us: 1) Accounts with more than 6 failed login attempts in a 10 minute period are disabled for 10 minutes. This makes brute force methods to find passwords almost impossible. 2) Limit to 200 outgoing messages per day per user. We'll raise it to

Re: Compromised Passwords

2014-03-06 Thread DTNX Postmaster
On 06 Mar 2014, at 18:04, Adam Moffett adamli...@plexicomm.net wrote: Two steps eliminated this problem for us: 1) Accounts with more than 6 failed login attempts in a 10 minute period are disabled for 10 minutes. This makes brute force methods to find passwords almost impossible. 2)

Re: Compromised Passwords

2014-03-06 Thread li...@rhsoft.net
Am 06.03.2014 18:04, schrieb Adam Moffett: Two steps eliminated this problem for us: 1) Accounts with more than 6 failed login attempts in a 10 minute period are disabled for 10 minutes. This makes brute force methods to find passwords almost impossible. that is fine 2) Limit to 200

Re: Compromised Passwords

2014-03-05 Thread tobi
Am 04.03.2014 23:38, schrieb Homer Wilson Smith: Change their password? from my experience the only thing that really stops the spam Maybe it's anoying for the account owner but it works most reliable. Counting IPs might help also but what if the spammer uses the same src ip for its

Re: Compromised Passwords

2014-03-05 Thread Blake Hudson
Homer Wilson Smith wrote the following on 3/4/2014 4:38 PM: Dear Gentle Folk, What is the state of the art in dealing with users whose SASL password has been compromised? Running CentOS, and latest postfix. When a password gets compromised, spam starts to pour out of the server

Re: Compromised Passwords

2014-03-05 Thread Venkat
I'm constantly facing the same problem (passwords comprimised, accounts abused). May you be so gentle to share your policyd configuration? It would be really helpful. Thank you in advanced. I sent you an email with our configuration/notes. If anyone else is interested, let me know. cheers,

Re: Compromised Passwords

2014-03-05 Thread lconrad
On Wednesday 05/03/2014 at 9:25 am, Blake Hudson wrote: Homer Wilson Smith wrote the following on 3/4/2014 4:38 PM: Dear Gentle Folk, What is the state of the art in dealing with users whose SASL password has been compromised? Running CentOS, and latest postfix.

RE: Compromised Passwords

2014-03-05 Thread Paul A
Sent: Wednesday, March 05, 2014 4:42 PM To: postfix-users@postfix.org Subject: Re: Compromised Passwords On Wednesday 05/03/2014 at 9:25 am, Blake Hudson wrote: Homer Wilson Smith wrote the following on 3/4/2014 4:38 PM: Dear Gentle Folk, What is the state of the art

Re: Compromised Passwords

2014-03-04 Thread Florian Pritz
On 04.03.2014 23:38, Homer Wilson Smith wrote: Rate limiting is interesting but doesn't really stop the spam. Use postfwd or similar to rate-limit to say 100 mails/recipients per 6 hours. If the limit is triggered look at the logs and if it looks like spammers disable the account and tell

Re: Compromised Passwords

2014-03-04 Thread Venkat
When a password gets compromised, spam starts to pour out of the server from endless numbers of IP's, to endless numbers of addresses. Rate limiting is interesting but doesn't really stop the spam. Counting client=[IP] addresses until a threshold is reached is highly effective,

Re: Compromised Passwords

2014-03-04 Thread LuKreme
On 04 Mar 2014, at 15:47 , Florian Pritz bluew...@xinu.at wrote: Use postfwd On 04 Mar 2014, at 20:24 , Venkat mvenkat...@gmail.com wrote: We are using policyd are there specific advantages/disadvantages with policed or postfw? They look like they can do much the same thing, so is there a

Re: Compromised Passwords

2014-03-04 Thread Rodolfo González González
El 04/03/2014 09:24 p.m., Venkat escribió: When a password gets compromised, spam starts to pour out of the server from endless numbers of IP's, to endless numbers of addresses. Rate limiting is interesting but doesn't really stop the spam. Counting client=[IP] addresses until a