From owner-freebsd-questions@freebsd.org Wed Mar 7 14:20:04 2018 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 9D759F30695 for ; Wed, 7 Mar 2018 14:20:04 +0000 (UTC) (envelope-from wfdudley@gmail.com) Received: from mail-yb0-x22a.google.com (mail-yb0-x22a.google.com [IPv6:2607:f8b0:4002:c09::22a]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 34699762F0 for ; Wed, 7 Mar 2018 14:20:04 +0000 (UTC) (envelope-from wfdudley@gmail.com) Received: by mail-yb0-x22a.google.com with SMTP id h19-v6so758248ybj.11 for ; Wed, 07 Mar 2018 06:20:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:cc; bh=al9ohFbklCbvyX+Fp6587NypdHx53Nf5maKPE4Guu6E=; b=Kuv0u/LP8dztBmwT00QZBy8F5vnfuoV6NT9CncZ3QULgsQSpLQHCQUQXJslgFQnfh2 YbQ8YtPb3wz3TQiR6pkyFgh8OLpHRIF3F9H2SC4ZmysAvcwfjHK2pFWrUCKYJsgcwTN9 n1L3NPxVRxc99mFIOVvMz9KL1ggJGze9lmb4XXl228gvgiagS+uQRDSAbFvDLwRp1KKo 6cDAl3YgwmnpLvm9gwrzwjp2mpJ3bSmLzfQmx4nv9Ydgy7UNxiHHNZdvXBaW3FgJZVFv LuLcH16FNfpQK1gw4bbV7XMb6Ziix+v10FiFMUiGUEwcn2PmUvYIiYe5guBkCt7pI4qZ BZ2g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:cc; bh=al9ohFbklCbvyX+Fp6587NypdHx53Nf5maKPE4Guu6E=; b=MrRruwPVAZ9PAUkyKm+VW1l7wQvCSHuGkN2p0iID+YW3SzNj+3Sdezkq2YgzkP1+dD lVGaN3ELNMJEF/BqW9fPyONblhw8kAQZ2slIYcddw1zDd1U9U4da2UWuH9OPRi+5GoFd JuOiubrpXPdCBJl3By8Ra4IwnZZFfNF+G97na1IzZSC8Ogeh4EEsynz38RxyLyby8Up/ zUcH6UOivom1Os4rGjOf2NsNzxugqgdoS5Ho2lwVFWgwa8VgRLIbkvatpMikZdeBmq12 DhBgqONNZrtOVLdCLkcIJM2pIJQQbipuc0AcnKZHRP+mHIXZYRb/6EDR8f1mTQ16YuHp j2ag== X-Gm-Message-State: APf1xPDupLgUvG6+bNuGPIT3dTxicpIp4nlqQ4EQDKjrKWcbevYO6D5P zbLe0wbta9pDbtKSlHrmyH7w/xc2XAJUfPwR7Vw= X-Google-Smtp-Source: AG47ELtjPRkCMmALcTXZuN/6Zqou9Km9YFRvKzgVD9TKLth91OUW7UrtXopbFYH7ZLMKJ8SlPaoTlfVfu1vnXuKideo= X-Received: by 2002:a25:67c6:: with SMTP id b189-v6mr13899097ybc.199.1520432403316; Wed, 07 Mar 2018 06:20:03 -0800 (PST) MIME-Version: 1.0 Received: by 2002:a25:324f:0:0:0:0:0 with HTTP; Wed, 7 Mar 2018 06:20:02 -0800 (PST) In-Reply-To: <20180307103136.25881537.ole@free.de> References: <20180307071944.GA30971@ymer.bara1.se> <20180307103136.25881537.ole@free.de> From: William Dudley Date: Wed, 7 Mar 2018 09:20:02 -0500 Message-ID: Subject: Re: Increased abuse activity on my server Cc: freebsd-questions Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 07 Mar 2018 14:20:04 -0000 This may sound stupid and obvious, but I moved my ssh port to a high "random" port number, and that completely stopped the random attempts to ssh in. I know that "security by obscurity" "doesn't work", but it did! I picked a port like 5792 -- not related to anything else. (i.e. don't pick 2222 or 2022 etc.) I've had this in place for months and months (perhaps a year) and the attackers haven't found the port yet. I think this works because unless you, specifically, are at *target* of somebody *serious*, (think "kbg"), most of these attackers are opportunists who won't spend the time to do a full port scan of your server. They just try the standard ports: 21, 22, 23, 25, etc. ALSO, you should disable password auth for ssh and use only public/private key. Then you know the attackers are REALLY wasting their time. Bill Dudley This email is free of malware because I run Linux. On Wed, Mar 7, 2018 at 4:31 AM, Ole wrote: > Wed, 7 Mar 2018 08:19:44 +0100 - User Hasse : > > > Anybody else noticed ? > > Welcome to the internet :-) > > If you have strong passwords or better only public key authentication > allowed, just don't care. If you want to increase security you could > use a VPN + Firewall to only allow connections from your VPN. If you > just don't want them to spam your logs you could just move sshd from > port 22 to port 24. > > regards Ole >