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-3
votes
1answer
31 views

How to prevent hackers from accessing my cPanel through a hostname instead of IP? [on hold]

On my new dedicated server in which I have cPanel and WHM, I keep getting daily "large number of failed attempts to login from xxx" where xxx is an IP. So I blocked massive amounts of entire IP ...
0
votes
1answer
26 views

How to prevent spam from “as permitted sender” senders?

Looking into my gmail spam folder, I see many messages coming from an old domain. How does it work, that I receive spam from an old account? And, how can I stop these spammers of using the old email ...
0
votes
1answer
27 views

Automatically defer certain messages in Postfix

Recently we've had a spate of "spear-phishing" attacks that many of our users have fallen for, and as a result our automated scripts are running at full steam locking accounts that have been ...
-1
votes
1answer
47 views

Exchange Server Spam Protection [closed]

I took over an exchange 2010 server on what I believe is a Hyper V Virtual Machine, running Windows Server 2008. We have a SonicWALL firewall, but the majority of the licensing on the firewall is no ...
-2
votes
0answers
39 views

How to bounce outgoing spam messages with postfix and spamassassin milter? [duplicate]

One of my email server users recently had their password compromised and resulted in my server briefly becoming a spam source. I finally managed to clear the blacklists and have implemented ...
-1
votes
0answers
76 views

Unable to Stop Mail Server Abuse [duplicate]

I have a mail server that has somehow been compromised. Its been well over a week and since then I have changed many settings to no avail. As a first step I saw the mail logs which indicated a high ...
0
votes
1answer
45 views

E-mail always send to spam folder [duplicate]

I have an VPS that has a pre-installed DirectAdmin and exim mailservice. But i've got a complainment from my client. When he tries and send an e-mail from his account to someone it gets flagged as ...
0
votes
1answer
46 views

Postscreen sometimes stops the mail

"The Postfix postscreen(8) server provides additional protection against mail server overload. One postscreen(8) process handles multiple inbound SMTP connections, and decides ...
0
votes
0answers
36 views

Postfix — auto blacklist senders who send to 'honeypot' email addresses [duplicate]

I'm using postfix + spamassassin (amavis) now and I'm trying to increase my hit rate, so I've been looking at the logs to try to see any patterns in email that is obvious spam but gets low scores. ...
-1
votes
1answer
45 views

Sometimes this script fails to update the iptables [closed]

It does not happen often, but sometimes after running the below script, checking the iptables with service iptables status shows that they weren't updated and the script doesn't output any error. The ...
-1
votes
1answer
59 views

mail server Best practices PTR and SPF

I have 2 domain names in my server : domain1.com is the main domain that I am using as a nameserver (ns1.domain1.com and ns2.domain1.com) and domain2.com (I am using it to host my web application ...
1
vote
1answer
49 views

create safe sender list based on domains of email recipients in Exchange

We're moving from Google Postini to Symantec Cloud as a spam filter. In Postini we've managed to collect a total number of about 3400 domains added over the years to our safe sender list. But ...
0
votes
1answer
38 views

How do I block a user doing too many requests without blocking an entire organization?

We have a running website and some of the content comes from a paid API. Our website is free. Our main concern at the moment is people using our website as a "free" way to get at the underlying data ...
0
votes
4answers
121 views

Create IP nullroute blacklist from text file

I've seen various guides out there for how to nullroute a single IP address, and I've done that before. However, I'm not sure how to nullroute a group of IP addresses. Going through each one ...
10
votes
2answers
676 views

How can I reduce the damage of stolen mail accounts?

Currently I’m offering some webhosting to a few advertising agencies for their premium customers. But currently I have a great problem with the E-Mail Service. In the last week, the E-Mail Accounts of ...
1
vote
0answers
43 views

How to check why SpamAssasin Bayes filter not working?

I have exim 4.77 with spamassasin 3.4.0 on Debian, I identify spams by myself and send to sa-learn, which seems working. But I have never receive spamscore by Bayes, I check the emails which ...
0
votes
1answer
52 views

PermError SPF Too Many Lookups and Reduction

My current SPF record is as follows: v=spf1 mx include:servers.mcsv.net include:xero.com -all The above cause the SPF validation to fail. Using http://mxtoolbox.com/SuperTool.aspx?action=txt, I ...
1
vote
1answer
329 views

Exchange 2010 email spoofing prevention

Masters, Unfortunately we got some spam mail which seems to be coming from our own domain. I found some article which all says to remove Anonymous login from internet receive connector ...
0
votes
1answer
672 views

GMail sends basic email to spam folder. SPF DKIM ok? [closed]

I am trying to send an email from my server using Mailgun. It's a very basic plain text email but for some reason it is ending up in spam. SPF and DKIM passes. Any ideas? I don't have any clue. This ...
1
vote
0answers
345 views

How can I test if my apache server is an open proxy?

Is there a curl command that will validate if a server is acting as an open proxy? I've tried curl --proxy http://<my server>:80 http://yahoo.com But the response from apache is: ...
0
votes
0answers
28 views

Prevent email spam from vhosts

We have a server with several vhosts (with php) running. Recently one vhost was overtaken from a "hacker" which manipulated the php scripts to send email spam. Because the other email servers blocked ...
0
votes
1answer
774 views

Filter spam emails from being forwarded by exim4

I was studying and searching 2 days about how to configure my exim/spamassassin/clamd configuration. I have the next situation: I have an email a@domain.com redirected to a@gmail.com. Unfortunately, ...
0
votes
0answers
85 views

SpamAssassin keeps crashing during cleanup of child pid due to SIGCHLD: interrupted, signal 2 (0002)

I am running SpamAssassin on an Ubuntu Server with a quad-core processor and 7.5GB RAM. I am running a Mail Server on a separate Windows Machine and this Mail Server passes messages to the ...
-1
votes
2answers
288 views

Postfix is Sending Spam [duplicate]

I have an Ubuntu 12.04 server, hosted on AWS, that powers a dozen WordPress installations using Nginx and php5-fpm. The problem just began one day. My server was down. Panic! Whenever I turned it on ...
0
votes
0answers
121 views

Incoming mail flagged as spam

A customer of my company can no longer contact us via mail. Our mailserver keeps bouncing their email as spam. I've already contacted them but they say the problem lies with our server, not with ...
2
votes
1answer
52 views

Simulating spam request?

I'm trying to test out some blacklist directives that I've just implemented., Is there a way to simulate spam requests?
1
vote
1answer
73 views

How to solve gmail spam filter issue

We have a problem when sending emails to "gmail.com" domain. All of our emails end up in spam folder. We do not send spam or bulk emails, so I would like to know is there a way to solve this issue. ...
1
vote
1answer
114 views

Mails marked as spam in gmail for some accounts

I have a couple of domains running on my VPS with VirtualMin. I have DKIM enabled, reverse DNS is setup and SPF records are added by Virtualmin. Now I have a main account (admin) which I can easily ...
6
votes
4answers
822 views

How can I block outside mail FROM postmaster@mydomain.com?

A security firm has been testing my mail server and claims my Postfix daemon is an open relay. The evidence is as follows (valid public IP for mail.mydomain.com has been changed to 10.1.1.1 for ...
0
votes
1answer
129 views

Postfix: don't bounce for remote rejects

I'm having a problem with sending bounces to spammers when a remote "trusted" smtp server rejects a mail. My server manages mail for company1.com that has a virtual alias support@company1.com that ...
1
vote
3answers
255 views

Are generic reverse DNS entries acceptable for an outgoing SMTP server?

Our PTR records are managed by our ISP, as our ranges are too small for them to consider delegating to us. So, every time I want to update an entry, I have to email their support team. In an effort ...
-1
votes
0answers
186 views

DKIM SPF passes but mail goes to Spam Received: (from abc@localhost)

I am facing an issue with the DKIM setup. We are sending newsletters which are going to spam in gmail. The dkim & spf passes. Even the reverse dns is setup properly. Below is a copy of mail ...
-2
votes
1answer
110 views

Using Spam Assassin as email proxy

I'm looking to setup a Spam Filter Proxy for my clients, not too many mind you, and have it as transparent as possible. I read about SAVASM and Spam Vigilante, and while they are perfect I guess for ...
0
votes
1answer
363 views

dkim-milter appears not to be signing my emails correctly in VirtualMin

I have a VPS that I had a fresh install of CentOS 6 on it and then I installed virtualmin on it and we've been great for a few months. I've been hosting a handful of domains from there and on one of ...
0
votes
0answers
209 views

Server is being used to send spam email via sendmail

When I run sudo tail -f /var/log/mail.log I can see a number of 'live' entries appearing such as Jun 6 00:40:03 ks393391 sm-msp-queue[2641]: r55MV0l1001642: to=ledbpw@gmail.com, ctladdr=www-data ...
0
votes
1answer
118 views

Global Authority for Blacklisting IPs

I know that there are few common ways to block attacking IPs (such as deny in htaccess). Additional to that, we could get a huge list of IPs to block from misc sites such as : ...
-1
votes
1answer
97 views

Sendmail mqueue deferred (list.dsbl.org) [closed]

Hi I have a issue with a mailserver configured with sendmail. In mailq I have many entrys with: (dnsbl map: lookup (254.0.168.192.list.dsbl.org.): deferred) Thanks.
2
votes
1answer
2k views

Whitelist rule for reject_rbl_client in Postfix?

Is there a way to add an exclusion/whitelist rule (or similar), which would work against reject_rbl_client behavior? I have a postfix service running, with following client restrictions: ...
1
vote
1answer
104 views

Open Proxy Spam Traffic

I have an apache server that was misconfigured and left as an open proxy for a week. A bunch of requests for forwarding pay-per-click advertising started streaming in and using our server. This ...
0
votes
1answer
223 views

Mail is marked as spam although SPF and DKIM pass

I have configured Postfix to send mail from a dedicated server hosted let's on IP X.X.X.X and domain name example.com. DKIM, SPF always pass when I send mail locally from that host but still ends up ...
0
votes
0answers
48 views

Uncontrolled spam sent from server [duplicate]

Hi I have shared hosting on a UK2 server that got suspended again. They claim that my account is sending SPAM messages but the problem is that I can't trace those from the information they've given me ...
0
votes
3answers
2k views

smtpd_helo_restrictions = …, reject_unknown_helo_hostname occasionally rejects mail I care about, how to handle?

I have configured my postfix as follows: smtpd_helo_restrictions = permit_sasl_authenticated, permit_mynetworks, reject_unknown_helo_hostname This is working well because most spambots don't seem ...
-1
votes
2answers
109 views

All Details of a Running Process [duplicate]

Possible Duplicate: How do I deal with a compromised server? This process is running on my Linux server and is sending spam (connecting to port 25 and port 80 with random IP's). top - ...
1
vote
1answer
260 views

Sending email from a Google Apps address

I have a website in a Linode VPS in Linode. The email address to receive emails is hosted in Google Apps, but I send emails from postfix. For that to work and not cause problems with spam folders, I ...
1
vote
2answers
166 views

How Reverse DNS does what it does

Hopefully this is not a stupid question, but I cannot find a clear cut answer. Can someone please inform me exactly what 'source address' is used in Reverse DNS? Does rDNS pull the IP address from ...
2
votes
2answers
325 views

Tons of spam on dreamhost mail user account

I use dreamhost for my webserver/ email host. I have about 25 users on one domain. and 1 of these users is absolutely inundated with spam every day. I have tried using dreamhosts poor blacklist ...
1
vote
3answers
1k views

How to block this URL pattern in Varnish VCL?

My website is getting badly hit by spambots and scrappers, I am using Cloudflare but the problem still remains there. The problem is spambots accessing non-existing urls causing a lot of load to my ...
34
votes
4answers
4k views

Is greylisting still an efficient method for preventing spam?

I've used greylisting on my servers for many years, but I don't know how effective it is nowadays. Is it still good for fighting spam in 2012? Or is the typical spammer MTA capable of resending ...
-4
votes
1answer
100 views

Stop BPimage walker bot [closed]

How can i block all bots except a few including BPImage walker...it is creating a huge amount of load on web site and consuming lots of bandwidth
66
votes
9answers
24k views

How to stop people from using my domain to send spam? [duplicate]

I receive Mailer Daemon messages saying certain emails fail. My domain is itaccess.org which is administered by Google apps. Is there any way I can identify who is sending emails from my domain, and ...