April 2003 - openSUSE Security - openSUSE Mailing Lists

how to keep nimda and code red from filling apache logs
by Mathias Homann 25 Sep '03

25 Sep '03

Hi all, here's a bit of a step-by-step description on how to keep nimda and codered from filling your apache logs. Parts used: - SuSE 7.2 Professional - SuSEfirewall2 - iptables 1.2.3 - linux kernel 2.4.13-pre5 steps: 1. install kernel sources for a kernel >> 2.4.9, running 2.4.13- pre5 here, works fine so far 2. get the sources for iptables 1.2.3 from http://netfilter.samba.org 3. unpack sources somewhere 4. export KERNEL_DIR=$(where you put the kernel tree) 5. cd into unpacked iptables sources, there's a subdirectory named patch-o-matic there 6. apply wanted patches by running ./runme $(name.of.patch)patch for this here You'll want the string patch You can also apply other patches, like the irc-conntrack patch 7. now there's a little bug in this patch... here's a diff: --- linux/net/ipv4/netfilter/ipt_string.c~ Sun Oct 21 00:16:29 2001 +++ linux/net/ipv4/netfilter/ipt_string.c Sun Oct 21 16:54:45 2001 @@ -62,7 +62,7 @@ sk = skip[haystack[right_end - i]]; sh = shift[i]; - right_end = max(int, right_end - i + sk, right_end + sh); + right_end = max(right_end - i + sk, right_end + sh); } return NULL; 8. now, make config/menuconfig/xconfig... as usual. You can import your running kernel's config first. 9. enable the experimental stuff 10. go to networking options->netfilter, there's an option there to enable string matching; set that to M 11. compile and install kernel as usual; remember to uncomment the export INSTALL_PATH=/boot in the main makefile. 12. now build a rpm file for the new iptables stuff by installing the source rpm which comes with suse, then edit the spec file, put the iptables source in /usr/src/packages/SOURCE and rebuild. 13. now there are some small changes to the firewall config files. a) uncomment the last line in /etc/rc.config.d/firewall2.rc.config: FW_CUSTOMRULES="/etc/rc.config.d/firewall2-custom.rc.config" b) edit that file, I got the following stuff in mine: for forbidden_string in root.exe cmd.exe .ida; do iptables -I input_ext -p tcp --dport http -m string \ --string $forbidden_string -m state \ --state ESTABLISHED -j REJECT --reject-with tcp-reset done put that in the last supfunction defined in the custom rc file. c) change the FW_LOG setting in firewall2.rc.config from reading -log-level warning to -log-level kernel.warning 14. last: some small changes to /sbin/SuSEfirewall2 search in the script for the parts where the modules are loaded and unloaded; be sure to add ipt_string (and the other new modules you created by patching the kernel and enabling them in make config) to the modules loading/unloading code there. 15. reboot 16. if you try now to access (from outside, of course) one of the nimda or codered URLS, all you get is a 'connection reset by peer', and the request doesn't show in apache log files. btw, no guarantees, and the usual YMMV :) bye [L]

7 7

SuSE Security Announcement: KDE (SuSE-SA:2003:026)
by Sebastian Krahmer 15 May '03

15 May '03

-----BEGIN PGP SIGNED MESSAGE----- ______________________________________________________________________________ SuSE Security Announcement Package: KDE Announcement-ID: SuSE-SA:2003:0026 Date: Thu Apr 24 12:00:00 MEST 2003 Affected products: 7.1, 7.2, 7.3, 8.0, 8.1, 8.2 SuSE eMail Server 3.1 SuSE eMail Server III SuSE Firewall Adminhost VPN SuSE Linux Admin-CD for Firewall SuSE Firewall on CD 2 - VPN SuSE Firewall on CD 2 SuSE Linux Connectivity Server SuSE Linux Enterprise Server 7 SuSE Linux Office Server Vulnerability Type: various security vulnerabilities Severity (1-10): 5 SuSE default package: yes Cross References: http://www.kde.org/info/security/advisory-20030409-1.txt http://www.kde.org/info/security/advisory-20021220-1.txt http://www.kde.org/announcements/announce-3.0.5a.html Content of this advisory: 1) security vulnerability resolved: Results of security audit of KDE. problem description, discussion, solution and upgrade information 2) pending vulnerabilities, solutions, workarounds: - glibc - pptpd 3) standard appendix (further information) ______________________________________________________________________________ 1) problem description, brief discussion, solution, upgrade information The K Desktop Environment KDE allows to generate postscript previews which can be viewed via certain konqueror plug-ins for example. The previews are generated by invoking the ghostscript program but without supplying the "-dSAFER" option as an argument. This allows embedded code to be executed. Additionally to the correction made to the postscript generation process, various other security related bug fixes and patches from KDE 3.0.5a have been incorporated. For more information regarding these fixes please visit the URLs given as cross references. The complete list of fixed packages is as follows: kdelibs3 kdelibs3-cups kdebase3 kdebase3-kdm kdebase3-konqueror kdebase3-ksysguardd kdebase3-extra kdegames3 kdegames3-board kdegraphics3-fax kdegraphics3-tex kdegraphics3-viewer kdegraphics3-postscript kdemultimedia3-midi kdemultimedia3-sound kdemultimedia3-video kdenetwork3 kdenetwork3-mail kdenetwork3-chat kdenetwork3-lan kdepim3-organizer kdepim3-kpilot kdesdk3 kdeutils3 kdeutils3-laptop Due to the large list of update packages we do not provide MD5 sums in this advisory. This would blow up the advisory and make it unreadable. Rather we recommend to either update your system via YaST2 where the auto updater automatically checks the integrity of the packages or to follow the guideline from section 3, "Package authenticity verification". Please download the update package for your distribution and verify its integrity by the methods listed in section 3) of this announcement. Then, install the package using the command "rpm -Fhv file.rpm" to apply the update. Our maintenance customers are being notified individually. The packages are being offered to install from the maintenance web. ______________________________________________________________________________ 2) Pending vulnerabilities in SuSE Distributions and Workarounds: - glibc New glibc packages will be available soon which fix a RPC XDR integer overflow. The packages are currently being tested. - pptpd A buffer overflow was found in the pptpd server. New packages will be available soon. ______________________________________________________________________________ 3) standard appendix: authenticity verification, additional information - Package authenticity verification: SuSE update packages are available on many mirror ftp servers all over the world. While this service is being considered valuable and important to the free and open source software community, many users wish to be sure about the origin of the package and its content before installing the package. There are two verification methods that can be used independently from each other to prove the authenticity of a downloaded file or rpm package: 1) md5sums as provided in the (cryptographically signed) announcement. 2) using the internal gpg signatures of the rpm package. 1) execute the command md5sum <name-of-the-file.rpm> after you downloaded the file from a SuSE ftp server or its mirrors. Then, compare the resulting md5sum with the one that is listed in the announcement. Since the announcement containing the checksums is cryptographically signed (usually using the key security(a)suse.de) the checksums show proof of the authenticity of the package. We disrecommend to subscribe to security lists which cause the email message containing the announcement to be modified so that the signature does not match after transport through the mailing list software. Downsides: You must be able to verify the authenticity of the announcement in the first place. If RPM packages are being rebuilt and a new version of a package is published on the ftp server, all md5 sums for the files are useless. 2) rpm package signatures provide an easy way to verify the authenticity of an rpm package. Use the command rpm -v --checksig <file.rpm> to verify the signature of the package, where <file.rpm> is the filename of the rpm package that you have downloaded. Of course, package authenticity verification can only target an un-installed rpm package file. Prerequisites: a) gpg is installed b) The package is signed using a certain key. The public part of this key must be installed by the gpg program in the directory ~/.gnupg/ under the user's home directory who performs the signature verification (usually root). You can import the key that is used by SuSE in rpm packages for SuSE Linux by saving this announcement to a file ("announcement.txt") and running the command (do "su -" to be root): gpg --batch; gpg < announcement.txt | gpg --import SuSE Linux distributions version 7.1 and thereafter install the key "build(a)suse.de" upon installation or upgrade, provided that the package gpg is installed. The file containing the public key is placed at the top-level directory of the first CD (pubring.gpg) and at ftp://ftp.suse.com/pub/suse/pubring.gpg-build.suse.de . - SuSE runs two security mailing lists to which any interested party may subscribe: suse-security(a)suse.com - general/linux/SuSE security discussion. All SuSE security announcements are sent to this list. To subscribe, send an email to <suse-security-subscribe(a)suse.com>. suse-security-announce(a)suse.com - SuSE's announce-only mailing list. Only SuSE's security announcements are sent to this list. To subscribe, send an email to <suse-security-announce-subscribe(a)suse.com>. For general information or the frequently asked questions (faq) send mail to: <suse-security-info(a)suse.com> or <suse-security-faq(a)suse.com> respectively. ===================================================================== SuSE's security contact is <security(a)suse.com> or <security(a)suse.de>. The <security(a)suse.de> public key is listed below. ===================================================================== ______________________________________________________________________________ The information in this advisory may be distributed or reproduced, provided that the advisory is not modified in any way. In particular, it is desired that the clear-text signature shows proof of the authenticity of the text. SuSE Linux AG makes no warranties of any kind whatsoever with respect to the information contained in this security advisory. Type Bits/KeyID Date User ID pub 2048R/3D25D3D9 1999-03-06 SuSE Security Team <security(a)suse.de> pub 1024D/9C800ACA 2000-10-19 SuSE Package Signing Key <build(a)suse.de> - -----BEGIN PGP PUBLIC KEY BLOCK----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: For info see http://www.gnupg.org mQGiBDnu9IERBACT8Y35+2vv4MGVKiLEMOl9GdST6MCkYS3yEKeueNWc+z/0Kvff 4JctBsgs47tjmiI9sl0eHjm3gTR8rItXMN6sJEUHWzDP+Y0PFPboMvKx0FXl/A0d M+HFrruCgBlWt6FA+okRySQiliuI5phwqkXefl9AhkwR8xocQSVCFxcwvwCglVcO QliHu8jwRQHxlRE0tkwQQI0D+wfQwKdvhDplxHJ5nf7U8c/yE/vdvpN6lF0tmFrK XBUX+K7u4ifrZlQvj/81M4INjtXreqDiJtr99Rs6xa0ScZqITuZC4CWxJa9GynBE D3+D2t1V/f8l0smsuYoFOF7Ib49IkTdbtwAThlZp8bEhELBeGaPdNCcmfZ66rKUd G5sRA/9ovnc1krSQF2+sqB9/o7w5/q2qiyzwOSTnkjtBUVKn4zLUOf6aeBAoV6NM CC3Kj9aZHfA+ND0ehPaVGJgjaVNFhPi4x0e7BULdvgOoAqajLfvkURHAeSsxXIoE myW/xC1sBbDkDUIBSx5oej73XCZgnj/inphRqGpsb+1nKFvF+rQoU3VTRSBQYWNr YWdlIFNpZ25pbmcgS2V5IDxidWlsZEBzdXNlLmRlPohcBBMRAgAcBQI57vSBBQkD wmcABAsKAwQDFQMCAxYCAQIXgAAKCRCoTtronIAKyl8sAJ98BgD40zw0GHJHIf6d NfnwI2PAsgCgjH1+PnYEl7TFjtZsqhezX7vZvYCIRgQQEQIABgUCOnBeUgAKCRCe QOMQAAqrpNzOAKCL512FZvv4VZx94TpbA9lxyoAejACeOO1HIbActAevk5MUBhNe LZa/qM2JARUDBRA6cGBvd7LmAD0l09kBATWnB/9An5vfiUUE1VQnt+T/EYklES3t XXaJJp9pHMa4fzFa8jPVtv5UBHGee3XoUNDVwM2OgSEISZxbzdXGnqIlcT08TzBU D9i579uifklLsnr35SJDZ6ram51/CWOnnaVhUzneOA9gTPSr+/fT3WeVnwJiQCQ3 0kNLWVXWATMnsnT486eAOlT6UNBPYQLpUprF5Yryk23pQUPAgJENDEqeU6iIO9Ot 1ZPtB0lniw+/xCi13D360o1tZDYOp0hHHJN3D3EN8C1yPqZd5CvvznYvB6bWBIpW cRgdn2DUVMmpU661jwqGlRz1F84JG/xe4jGuzgpJt9IXSzyohEJB6XG5+D0BiF0E ExECAB0FAjxqqTQFCQoAgrMFCwcKAwQDFQMCAxYCAQIXgAAKCRCoTtronIAKyp1f AJ9dR7saz2KPNwD3U+fy/0BDKXrYGACfbJ8fQcJqCBQxeHvt9yMPDVq0B0W5Ag0E Oe70khAIAISR0E3ozF/la+oNaRwxHLrCet30NgnxRROYhPaJB/Tu1FQokn2/Qld/ HZnh3TwhBIw1FqrhWBJ7491iAjLR9uPbdWJrn+A7t8kSkPaF3Z/6kyc5a8fas44h t5h+6HMBzoFCMAq2aBHQRFRNp9Mz1ZvoXXcI1lk1l8OqcUM/ovXbDfPcXsUVeTPT tGzcAi2jVl9hl3iwJKkyv/RLmcusdsi8YunbvWGFAF5GaagYQo7YlF6UaBQnYJTM 523AMgpPQtsKm9o/w9WdgXkgWhgkhZEeqUS3m5xNey1nLu9iMvq9M/iXnGz4sg6Q 2Y+GqZ+yAvNWjRRou3zSE7Bzg28MI4sAAwYH/2D71Xc5HPDgu87WnBFgmp8MpSr8 QnSs0wwPg3xEullGEocolSb2c0ctuSyeVnCttJMzkukL9TqyF4s/6XRstWirSWaw JxRLKH6Zjo/FaKsshYKf8gBkAaddvpl3pO0gmUYbqmpQ3xDEYlhCeieXS5MkockQ 1sj2xYdB1xO0ExzfiCiscUKjUFy+mdzUsUutafuZ+gbHog1CN/ccZCkxcBa5IFCH ORrNjq9pYWlrxsEn6ApsG7JJbM2besW1PkdEoxak74z1senh36m5jQvVjA3U4xq1 wwylxadmmJaJHzeiLfb7G1ZRjZTsB7fyYxqDzMVul6o9BSwO/1XsIAnV1uuITAQY EQIADAUCOe70kgUJA8JnAAAKCRCoTtronIAKyksiAJsFB3/77SkH3JlYOGrEe1Ol 0JdGwACeKTttgeVPFB+iGJdiwQlxasOfuXyITAQYEQIADAUCPGqpWQUJCgCCxwAK CRCoTtronIAKyofBAKCSZM2UFyta/fe9WgITK9I5hbxxtQCfX+0ar2CZmSknn3co SPihn1+OBNyZAQ0DNuEtBAAAAQgAoCRcd7SVZEFcumffyEwfLTcXQjhKzOahzxpo omuF+HIyU4AGq+SU8sTZ/1SsjhdzzrSAfv1lETACA+3SmLr5KV40Us1w0UC64cwt A46xowVq1vMlH2Lib+V/qr3b1hE67nMHjysECVx9Ob4gFuKNoR2eqnAaJvjnAT8J /LoUC20EdCHUqn6v+M9t/WZgC+WNR8cq69uDy3YQhDP/nIan6fm2uf2kSV9A7ZxE GrwsWl/WX5Q/sQqMWaU6r4az98X3z90/cN+eJJ3vwtA+rm+nxEvyev+jaLuOQBDf ebh/XA4FZ35xmi+spdiVeJH4F/ubaGlmj7+wDOF3suYAPSXT2QAFEbQlU3VTRSBT ZWN1cml0eSBUZWFtIDxzZWN1cml0eUBzdXNlLmRlPokBFQMFEDbhLUfkWLKHsco8 RQEBVw4H/1vIdiOLX/7hdzYaG9crQVIk3QwaB5eBbjvLEMvuCZHiY2COUg5QdmPQ 8SlWNZ6k4nu1BLcv2g/pymPUWP9fG4tuSnlUJDrWGm3nhyhAC9iudP2u1YQY37Gb B6NPVaZiYMnEb4QYFcqv5c/r2ghSXUTYk7etd6SW6WCOpEqizhx1cqDKNZnsI/1X 11pFcO2N7rc6byDBJ1T+cK+F1Ehan9XBt/shryJmv04nli5CXQMEbiqYYMOu8iaA 8AWRgXPCWqhyGhcVD3LRhUJXjUOdH4ZiHCXaoF3zVPxpeGKEQY8iBrDeDyB3wHmj qY9WCX6cmogGQRgYG6yJqDalLqrDOdmJARUDBRA24S0Ed7LmAD0l09kBAW04B/4p WH3f1vQn3i6/+SmDjGzUu2GWGq6Fsdwo2hVM2ym6CILeow/K9JfhdwGvY8LRxWRL hn09j2IJ9P7H1Yz3qDf10AX6V7YILHtchKT1dcngCkTLmDgC4rs1iAAl3f089sRG BafGPGKv2DQjHfR1LfRtbf0P7c09Tkej1MP8HtQMW9hPkBYeXcwbCjdrVGFOzqx+ AvvJDdT6a+oyRMTFlvmZ83UV5pgoyimgjhWnM1V4bFBYjPrtWMkdXJSUXbR6Q7Pi RZWCzGRzwbaxqpl3rK/YTCphOLwEMB27B4/fcqtBzgoMOiaZA0M5fFoo54KgRIh0 zinsSx2OrWgvSiLEXXYKiEYEEBECAAYFAjseYcMACgkQnkDjEAAKq6ROVACgjhDM /3KM+iFjs5QXsnd4oFPOnbkAnjYGa1J3em+bmV2aiCdYXdOuGn4ZiQCVAwUQN7c7 whaQN/7O/JIVAQEB+QP/cYblSAmPXxSFiaHWB+MiUNw8B6ozBLK0QcMQ2YcL6+Vl D+nSZP20+Ja2nfiKjnibCv5ss83yXoHkYk2Rsa8foz6Y7tHwuPiccvqnIC/c9Cvz dbIsdxpfsi0qWPfvX/jLMpXqqnPjdIZErgxpwujas1n9016PuXA8K3MJwVjCqSKI RgQQEQIABgUCOhpCpAAKCRDHUqoysN/3gCt7AJ9adNQMbmA1iSYcbhtgvx9ByLPI DgCfZ5Wj+f7cnYpFZI6GkAyyczG09sE= =LRKC - -----END PGP PUBLIC KEY BLOCK----- -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv iQEVAwUBPqe3R3ey5gA9JdPZAQEQOAf+MU36o5Osrr/Dt5D+q+slnnydUkcqTb6h lohbbUys6O9FYAbEQKZ4jwlT9Cg7+Z19FHF4wjVm3N9/VDU7uzdcOkE2mVwHh3cD OHEEG3cXj099wmj2MXnPkCQQothtrSAFa6OJ9mdw5jzeb8XIi6vXi/4HdtJU7BiY sVXkPTEEhzZQKjtHq1KotFWXSf7AMq4YB5Gtd1ob1hCTUdba7ScvGxbcKopGYlZf cepYOpM9WInfRFVZBeP1lpWEvG5BViESv/KxBrEaxyQCYsZjf1jkGCTLgmCk+/X4 RDjkzw8tgZFBrIv5+7L3I/H1hJ9sNTEPjkkPAJiSnX3ceT4ltmHWYA== =ZHNK -----END PGP SIGNATURE----- -- ~ ~ perl self.pl ~ $_='print"\$_=\47$_\47;eval"';eval ~ krahmer(a)suse.de - SuSE Security Team ~

5 6

iptables config
by Grutsch, Gerhard 03 May '03

03 May '03

Hi, i have got : network A with ip adress room 192.168.x.x (this side also connects to the internet) network B with ip adress room 10.x.x.x (my internal LAN) and a router with is a Linux box to connect the 2 lans via routing. So far so good, the traffic is running between the 2 networks, since i configures the routes on both networks. ------------| |------------ | | LAN A |-----------------------ROUTER---------------| LAN B | | ------------- -------------- My problem is though, i have no restrictions! I know the first few commands like : iptables -P FORWARD DROP, but i want to regulate, that WKS_A from LAN_A can communicate with WKS_1 from LAN_B but not with WKS_2 from LAN_B. Or that WKS_1 on LAN_A is allowed to use SSH ánd nothing else, but WKS_2 on LAN_A can use all tcp/ip services....... Thanx a lot in advance Gerhard Grutsch Support services Tel : 089/55878-151 Mobile : 0172-8391368 E-mail : ggrutsch(a)statestreet.com

4 3

Can't make losetup mount a crypto file to the loopback device (SuSE 8.2)
by Bo Jacobsen 01 May '03

01 May '03

I'm trying to mount a file to the loopback device but the losetup command complains about it. I'm using the command line: losetup -e twofish /dev/loop0 /root/testfile losetup asks for a password but returns: ioctl: LOOP_SET_STATUS: invalid argument when one is entered "losetup -e none" works I have tried with the standard kernel in SuSE 8.2 but also kernel 2.4.20-13 with both "loopback device support" and "Twofish encryption for loopback device" compiled into the kernel. Any suggestions. Thanks in advance Bo Jacobsen

3 4

Snort
by Richard Ibbotson 01 May '03

01 May '03

Hi Would anyone at SuSE or anyone else like to make a comment about the following on the Snort home pages ... http://www.snort.org/ .... news page Snort Advisory: Integer Overflow in Stream4 Brian @ Wed Apr 16 14:52:33 EDT 2003 Affected Versions: # All versions of the following products are affected: Snort 1.8 through 1.9.1 # Snort CVS - current branch up to version 2.0.0 beta I notice that SuSE 8.2 uses Snort Version 1.9.1 (Build 231) By Martin Roesch (roesch(a)sourcefire.com, www.snort.org) Will there be an update soon or is the SuSE version of Snort not vulnerable to this bug ? Thanks -- Richard www.sheflug.co.uk

2 2

updatedb@locate
by Sourian 01 May '03

01 May '03

I understand. Why is it no longer installed by default? Is it replaced by something else? If I need to search for a command, how can I do it? Best regards, Sourian

4 3

RE: [suse-security] updatedb@locate
by Punt, Ryan 30 Apr '03

30 Apr '03

I think the easier/more efficient answer to Q3 is "which", as in `which $command_you\'re_searching_for`. ~rlp -----Original Message----- From: Martin Peikert [mailto:lists@nolog.org] Sent: Wednesday, April 30, 2003 7:17 AM To: suse-security(a)suse.com Subject: Re: [suse-security] updatedb@locate Sourian wrote: > I understand. Why is it no longer installed by default? Is it > replaced by something else? If I need to search for a command, how > can I do it? Q1 + Q2: Ask SuSE. Q3: Install the needed packages or try find / -name command_you_need (please don't tell me that find is not installed by default ;) -- Public Key: http://www.tschetter.org/~ryan/ryan_punt.asc

2 1

SuSE and VSFTP
by suseuser＠blackcatsys.plus.com 30 Apr '03

30 Apr '03

I'm having some fun with SuSE and FTP. If the firewall on the server is turned off, the client works perfectly happily. But if the firewall on the server is turned on, it won't. I have opened up both 20 and 21 TCP and UDP to a limited IP range (within my network), but it just won't have any of it. I can log in, but I can't ls or change directory. Anyone got any suggestions? Many thanks in advance. D.

5 4

iptables and mysql
by Markus 29 Apr '03

29 Apr '03

Hi, I am running a mysql and http server. Now I would like to block all connections to mysql (tcp 3306). (Only connections from localhost to localhost are allowed). The http-port (tcp 80) should be reachable by everybody. So I made the following: #emty ip-table iptables --flush #accept everything from localhost to localhost iptables -A INPUT -p all -s localhost -d localhost -j ACCEPT #block mysql (tcp 3306) iptables -A INPUT -p tcp --destination-port 3306 -j REJECT Well, connections from outside are blocked, BUT: 1) nmap says tcp/3306 (mysql) filtered 2) in my xconsole (and tty10) the following warning appears: <date> <time> <my-pc> mysqld-max[1156]: warning: can't get client address: Connection reset by peer Now would like to know, why does nmap know that the port is filtered? And why does mysql notices that there was a connectionrequest, althought it was blocked? Thx Markus

3 2

Re: [suse-security] New logging message
by Matthias Riese 29 Apr '03

29 Apr '03

Thanks for the answers so far. So NOQUEUE: [218.79.178.192] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA is nothing to worry about. However I'm very worried about the PAM-warn[19900]: user: (uid=0) -> admin [remote: ?nobody@?nowhere] messages. It looks to me as if someone already has gained root rights and made an su to "admin" (which should be impossible, because /etc/passwd as I see it doesn't contain that user). I hope to be misleaded... Best regards, Matthias

1 0