<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">OK, great. Thanks Michael and Steven!<br><div>
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="font-weight: normal; "><br class="Apple-interchange-newline">--</div><div><b>Matt James</b></div><div style="font-weight: normal; "><a href="http://rainstorminc.com">RainStorm, Inc</a></div><div style="font-weight: normal; ">(207) 866-3908 x54</div></span></div></span></div></div></div></div></div>
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<br><div><div>On Jun 9, 2014, at 3:52 PM, Michael Stauber <<a href="mailto:mstauber@blueonyx.it">mstauber@blueonyx.it</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hi Matt,<br><br><blockquote type="cite">Last night, I performed some overdue yum updates to one of our dev<br>servers. Since the update, using SSH tunneling to log in to MySQL<br>has stopped working. The error I get is: Lost connection to MySQL<br>server at 'reading initial communication packet', system error: 0.<br></blockquote><br>Yeah, we turned that off as there was a creative way to use TCP<br>forwarding for spamming. It still required that someone knew or had<br>brute-forced login details of a user. But once they had it, they could<br>use TCP forwarding to send SPAM as that user even if the user in<br>question had no shell access. Which then was pretty difficult to detect<br>based on the logfiles alone.<br><br>See: "[BlueOnyx:15118] OpenSSL (CenOS-6.5/SL-6.5) CVE-2014-0160" and<br>following.<br><br>You can enable TCP forwarding on a per user basis as outlined here:<br>"[BlueOnyx:15096] Re: Securing against invading spammers"<br><br>It is possible to set certain SSH options on a per-user basis in<br>sshd_config - such as this:<br><br>Match User xyz<br> X11Forwarding no<br> AllowTcpForwarding yes<br><br>That would allow TCP forwarding for user "xyz", but for nobody else.<br><br>-- <br>With best regards<br><br>Michael Stauber<br>_______________________________________________<br>Blueonyx mailing list<br><a href="mailto:Blueonyx@mail.blueonyx.it">Blueonyx@mail.blueonyx.it</a><br>http://mail.blueonyx.it/mailman/listinfo/blueonyx<br></blockquote></div><br></body></html>