How to identify and prevent phishing email

How to identify and prevent phishing email

Well in the last few days, some people reported that they got an email from a CEO company, saying that the CEO wants to talk to him (perhaps to discuss a secret project? lol :-p). see the email below. phishing email from a CEO This email is suspicious, because: He never had any contact with the CEO beforeThe email goes into the spam folderToo good to be true? I had this experience before, and asked him to check the reply-to section of the email. And tadaa... it turns out that the "reply-to" address is different than the "from" email address. Well, without further due, we just reported SPAM email. reply-to email address HOW phishing email happens? Phising email diagram A phishing email attack is not new. Its been there since many years ago. This attack happens by exploiting the flaw in email protocol (SMTP - simple mail transport protocol). The SMTP protocol does not require to have a strict checking on the sender. Meaning, when you send an...
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Troubleshoot: zimbraRemoteManagementPrivateKeyPath (/opt/zimbra/.ssh/zimbra_identity) does not exist

Troubleshoot: zimbraRemoteManagementPrivateKeyPath (/opt/zimbra/.ssh/zimbra_identity) does not exist

Ketika konfigurasi Zimbra, saya nemu error ini: zimbraRemoteManagementPrivateKeyPath (/opt/zimbra/.ssh/zimbra_identity) does not exist. Akibatnya, beberapa fungsi di zimbra ada yang ngak jalan, beberapa command juga ada yang ngak jalan. Dari errornya kliatannya ini ada hubungannya dengan SSH, dimana user zimbra harus mempunyai key untuk berhubungan dengan aplikasi. dan aplikasi harus dapat mengakses server zimbra via ssh dengan user zimbra menggunakan key-based authentication (jadi ngak perlu ditanyain password lagi). setup troubleshooting: pastikan openssh running di port 22 switch menjadi user zimbra: su - zimbra setup parameter zimbra: zmprov ms hostname.domain.com zimbraRemoteManagementPort 22 generate ssh key untuk user zimbra: zimbra$ zmsshkeygen setup zimbra agar menggunakan key yang barusan dibuat zimbra$ zmupdateauthkeys semoga berguna bagi pembaca ...
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Mengirim email via email relay

Mengirim email via email relay

Email relay. Jadi critanya, saya lagi bingung konfigurasi mail server saya, kenapa ngak bisa ngirim email ke google atau lainnya. Seharusnya hal ini tidak menjadi masalah, karena protokol SMTP untuk ngirim email bisa langsung dipakai oleh komputer apapun termasuk laptop. nah mail server saya ini berada didalam jaringan telkom (speedy), menggunakan modem sebagai gatewaynya. saya coba kirim beberapa kali tapi hasilnya not delivered. hmmm ada something wrong disini… (more…)...
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Email blacklist dan cara mengeceknya

Email blacklist dan cara mengeceknya

Jika anda seorang administrator sebuah email server, maka anda mesti berusaha sekuat tenaga agar email server anda jangan sampai masuk dalam daftar email blacklist. hehehe Sekali server anda masuk dalam daftar blacklist, maka komplain akan datang bertubi-tubi dan usaha untuk mengeluarkan dari daftar blacklist tersebut juga tidak mudah. Sehingga, usaha preventif sangat disarankan agar terhindar dari blacklist. (more…)...
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What is open relay email server?

What is open relay email server?

Open-relay email server? What is that? In the last few days, I was involved in the troubleshooting of an email server of an organization. I was doing this remotely because I am still in Australia, and they are an 8-hours flight from here, located in a different country. So the point is, their email server is having severe issues. The network traffic rose suddenly, got a massive amount of email sending or receiving (very unusual), the amount is so huge, which causing legitimate users having a hard time accessing their email service. Well, after checking here and there, spending an amount of time troubleshooting, tadaaa..... it turns out that the email server is an open relay. What is Open relay? Open relay means a server allows an external party (outside the defined network) to send email through the server, and the server becomes like a repeater that relays/forward an email from outside to another email server. That is precisely how a relay works, right?...
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