From owner-freebsd-security@FreeBSD.ORG Thu Feb 16 19:01:29 2012 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3227E1065673 for ; Thu, 16 Feb 2012 19:01:29 +0000 (UTC) (envelope-from glen.j.barber@gmail.com) Received: from mail-vx0-f182.google.com (mail-vx0-f182.google.com [209.85.220.182]) by mx1.freebsd.org (Postfix) with ESMTP id DACAC8FC0A for ; Thu, 16 Feb 2012 19:01:28 +0000 (UTC) Received: by vcmm1 with SMTP id m1so2522860vcm.13 for ; Thu, 16 Feb 2012 11:01:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:x-operating-system :user-agent; bh=Tt6zLjHJISHETwGhy70EWNyxF7aJOpjhElA9JnejNSk=; b=Mkti2NXCqQRYq/DadXdkZ3/ZNjlwxm+AMP7ZoBFiUuc/dAC2ceVSXtEJHcZmF76gHc Ns0jMyOaFTxantCGkJ7wCBuKsfPkwWYgWgJooejUPkYaKE+65d0z+Ir017YTPulp3G2A 6AynVKrw6kIqNugwNEtCDm3bejxQ6A4c75iPc= Received: by 10.52.27.1 with SMTP id p1mr1802315vdg.17.1329418887417; Thu, 16 Feb 2012 11:01:27 -0800 (PST) Received: from schism.local (75-146-225-65-Philadelphia.hfc.comcastbusiness.net. [75.146.225.65]) by mx.google.com with ESMTPS id eg10sm4662331vdc.7.2012.02.16.11.01.26 (version=SSLv3 cipher=OTHER); Thu, 16 Feb 2012 11:01:26 -0800 (PST) Date: Thu, 16 Feb 2012 14:01:24 -0500 From: Glen Barber To: Miroslav Lachman <000.fbsd@quip.cz> Message-ID: <20120216190124.GB1989@schism.local> References: <4F3D3722.2000904@quip.cz> <20120216172652.GA1989@schism.local> <4F3D441A.4040303@quip.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4F3D441A.4040303@quip.cz> X-Operating-System: FreeBSD 10.0-CURRENT amd64 User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-security@freebsd.org Subject: Re: periodic security run output gives false positives after 1 year X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 16 Feb 2012 19:01:29 -0000 On Thu, Feb 16, 2012 at 06:59:54PM +0100, Miroslav Lachman wrote: > Glen Barber wrote: > > On Thu, Feb 16, 2012 at 06:04:34PM +0100, Miroslav Lachman wrote: > >> Hi, > >> > >> I see it many times before, but never take a time to post about it. > >> > >> Scrips in /etc/periodic are grepping logs for yesterday date, but > >> without specifying year (because some logs do not have year logged). > >> > >> This results in false positive alerts in security e-mails from our > >> lightly loaded servers, where logs are not enough rotated. > >> > >> For example /var/log/auth.log is 62KB (838 lines) and contains entries > >> for almost 2 years. > >> > >> Today I get following alert: > >> > >> Feb 15 22:36:03 XXX sshd[89758]: Invalid user t1na from xxx.xxx.xxx.xxx > >> Feb 15 22:50:56 XXX sshd[89850]: Invalid user medina from xxx.xxx.xxx.xxx > >> Feb 15 22:50:57 XXX sshd[89852]: Invalid user student from xxx.xxx.xxx.xxx > >> Feb 15 22:50:58 XXX sshd[89854]: Invalid user student from xxx.xxx.xxx.xxx > >> > >> (hostname and IP are replaced by X) > >> > >> But looking in to auth.log I found zero entries from yesterday - Feb 15 > >> entries were logged 1 year ago! > >> > >> So I propose to set all daemons / syslog to log year too (as %Y) and > >> change yesterday=`date -v-1d "+%b %e "` to yesterday=`date -v-1d "+%b > >> %e %Y"` in periodic scripts. > >> > >> The affected scripts are: > >> 460.status-mail-rejects > >> 470.status-named > >> 800.loginfail > >> 900.tcpwrap > >> > >> Maybe some others, I did just a quick grep -rsn 'date -v-1d' > >> /etc/periodic and I don't know the logic used in other script to get > >> yesterday messages. > >> > >> What do you think about it? > >> > > > > Rotating the appropriate logs daily/weekly/monthly/whatever will silence > > these false alarms. > > My post was not about "how can I fix it localy", but what sould be done > in FreeBSD distribuition, because these false alerts were made by > default FreeBSD configuration (coincidence of newsyslog settings, > periodic scripts and log format) > IMHO, this isn't something the FreeBSD installation can "guess" as a suitable default, but up to the administrator to define what is appropriate for their system. Glen