Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2005.0644 -- HP Security Bulletin HPSBUX01164 SSRT4884 rev.6 - HP-UX TCP/IP Remote Denial of Service (DoS) 18 August 2005 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: TCP/IP Publisher: Hewlett-Packard Operating System: HP-UX B.11.23 and prior Impact: Denial of Service Access: Remote/Unauthenticated CVE Names: CAN-2005-1192 CAN-2004-1060 CAN-2004-0791 CAN-2004-0790 Ref: ESB-2005.0575 ESB-2005.0409 Original Bulletin: http://h20293.www2.hp.com/cgi-bin/swdepot_parser.cgi/cgi/displayProductInfo.pl?productNumber=B6834AA - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 HP SECURITY BULLETIN HPSBUX01164 REVISION: 6 SSRT4884 rev.6 - HP-UX TCP/IP Remote Denial of Service (DoS) NOTICE: The information in this Security Bulletin should be acted upon as soon as possible. INITIAL RELEASE: 15 August 2005 POTENTIAL SECURITY IMPACT: Remote Denial of Service (DoS) SOURCE: Hewlett-Packard Company HP Software Security Response Team VULNERABILITY SUMMARY: A potential security vulnerability has been identified with HP-UX running TCP/IP. This vulnerability could be remotely exploited by an unauthorized user to cause a Denial of Service(DoS). REFERENCES: NISCC VU#532967, CAN-2004-0790, CAN-2004-0791, CAN-2004-1060 SUPPORTED SOFTWARE VERSIONS*: ONLY impacted versions are listed. HP-UX B.11.00, B.11.04, B.11.11, B.11.22, B.11.23 running TCP/IP. HP-UX B.11.11 and B.11.23 running TOUR (Transport Optional Upgrade Release). BACKGROUND: As reported in NISCC VU#532967 ICMP messages may be used to attack TCP/IP connections. <http://www.uniras.gov.uk/niscc/docs/ al-20050412-00308.html?lang=en> There are three issues reported in NISCC VU#532967: CVE number: CAN-2004-0790 <http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0790> CVE number: CAN-2004-0791 <http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0791> CVE number: CAN-2004-1060 <http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-1060> AFFECTED VERSIONS HP-UX B.11.00 ============= Networking.NET2-KRN action: install PHNE_33395, optionally set ip_pmtu_strategy=0 HP-UX B.11.04 ============= Networking.NET2-KRN ->action: install PHNE_33427, optionally set ip_pmtu_strategy=0 HP-UX B.11.11 ============= Networking.NET2-KRN action: install PHNE_33159, optionally set ip_pmtu_strategy=0 HP-UX B.11.22 ============= Networking.NET2-KRN action: install binary files, optionally set ip_pmtu_strategy=0 HP-UX B.11.23 ============= Networking.NET2-KRN action: install PHNE_32606, optionally set ip_pmtu_strategy=0 HP-UX B.11.11 HP-UX B.11.23 ============= TOUR_PRODUCT.T-NET2-KRN action: set ip_pmtu_strategy= 0 and filter ICMP END AFFECTED VERSIONS ->Note: The latest TOUR (Transport Optional Upgrade Release) -> functionality is available as follows: -> B.11.11 TOUR version 2.4 upgrade -> B.11.23 contained in the -> HP-UX 11i v2 September 2004 release ->Customers who wish to continue using an earlier version of TOUR ->on B.11.23 should apply the workaround (set ip_pmtu_strategy= 0 ->and filter ICMP). ->Customers who are able to update to the latest TOUR ->functionality in B.11.23 should upgrade to the HP-UX 11i v2 -> September 2004 release. ->After upgrading the action for B.11.23 Networking.NET2-KRN ->listed above should be implemented. RESOLUTION: Patches are available for the core network product from <http://itrc.hp.com>: For B.11.00 - PHNE_33395 or subsequent -> For B.11.04 - PHNE_33427 or subsequent For B.11.11 - PHNE_33159 or subsequent For B.11.23 - PHNE_32606 or subsequent Binary files are available for B.11.22 (details are below). Optionally set ip_pmtu_strategy=0. Please see the discussion below, "Workaround for CAN-2004-1060 may not be necessary." Note: If the TOUR (Transport Optional Upgrade Release) product is installed the binary files cannot be used. Until the TOUR product is revised there are several options: B.11.11 1. Use the workarounds. or 2. Remove TOUR and install the patch. B.11.23 1. Use the workarounds. or 2. Upgrade to the HP-UX 11i v2 September 2004 release and install the patch. TOUR(Transport Optional Upgrade Release) is available from <http://www.hp.com/go/softwaredepot>. Workaround for CAN-2004-1060 may not be necessary. =================================== Although changes in the binary files and patches for CAN-2004-0790 and CAN-2004-0791 do not prevent the exploit of CAN-2004-1060, they do make it less likely to succeed. The sequence number check suggested in section 5.1 of 'ICMP attacks against TCP' has been implemented. The Internet Draft of 'ICMP attacks against TCP' can be found here: <http://www.gont.com.ar/drafts/icmp-attacks-against-tcp.html>. Customers should consider whether this check reduces the risk of the exploit to the point that setting ip_pmtu_strategy=0 is not required. Note: ip_pmtu_strategy=0 sets the PMTU to 576 bytes and -> clears the "Don't Fragment" bit. This disables -> PMTU discovery. For IPv4 the Next-Hop MTU may be as low as 68 bytes. Therefore setting ip_pmtu_strategy=0 may cause -> performance to decrease. If the workaround for CAN-2004-1060 is to be used, please note the following: ================================================= HPSBUX01137 recommends setting ip_pmtu_strategy = 0 or 3 as a workaround for the problem of CAN-2005-1192. CAN-2004-1060 has a different root cause and cannot be worked around with p_pmtu_strategy=3. To work around both CAN-2005-1192 and AN-2004-1060 ip_pmtu_strategy=0 must be used. Please refer to the Manual Actions section below for a summary of the required actions. Workarounds: CAN-2004-0790 and CAN-2004-0791 Filter out the following ICMP messages: Type 3, Code 2 (Destination Unreachable, Protocol Unreachable) Type 3, Code 3 (Destination Unreachable, Port Unreachable) Type 4, Code 0 (Source Quench) CAN-2004-1060 Set ip_pmtu_strategy=0. Note: Filtering "Protocol Unreachable" and "Port Unreachable" should not be done without careful testing. Filtering these out may interfere with the correct functioning of network components. Filtering "Source Quench" should present little risk. Setting ip_pmtu_strategy=0 ================== Edit /etc/rc.config.d/nddconf to add the following: TRANSPORT_NAME[n]=ip NDD_NAME[n]=ip_pmtu_strategy NDD_VALUE[n]=0 where 'n' is the next available index value as described in the nddconf comments. This value will take effect when the system is rebooted. Until the system can be rebooted use the following command to read the /etc/rc.config.d/nddconf file and set the tunable parameters: /usr/bin/ndd -c The ip_pmtu_strategy parameter can be displayed by the following command: /usr/bin/ndd -get /dev/ip ip_pmtu_strategy Note: Since open connections will remain potentially vulnerable until they are closed and certain internal data structures are released it is recommended that the system be rebooted. Note: There is a defect that will cause "ndd -c" to fail if there are more than 10 directives in /etc/rc.config.d/nddconf. That defect is fixed in the following patches: B.11.11 - PHNE_25644 or subsequent B.11.04 - PHNE_26076 or subsequent B.11.00 - PHNE_26125 or subsequent Preliminary binary files ============== Preliminary binary files are available for B.11.22. Patches are available for B.11.00, B.11.11 and B.11.23. The patches and the preliminary binary files address CAN-2004-0790 and CAN-2004-0791 only. Although changes in the patches and binary files for CAN-2004-0790 and CAN-2004-0791 do not prevent the exploit of CAN-2004-1060, they do make it less likely to succeed. Instructions for downloading and installing the binary files are contained in readme files available here: System: hprc.external.hp.com (188.8.131.52) Login: icmp Password: icmp FTP Access: ftp://icmp:email@example.com/ or: ftp://icmp:firstname.lastname@example.org/ Note: The links above may not work for all browsers. If the link fails the url should be entered directly into the browser's address field. Since a patch is available for B.11.00 the readme.11.00.txt and corresponding binary files have been removed from the ftp site. Since a patch is available for B.11.11 the readme.11.11.txt and corresponding binary files have been removed from the ftp site. Since a patch is available for B.11.23 the readme.11.23.txt and corresponding binary files have been removed from the ftp site. Download the appropriate readme file containing further instructions: readme.11.22.txt Verify the cksum or md5sum: Note: The readme files have not changed since rev.1 of this Security Bulletin. cksum readme* 2836317466 2469 readme.11.22.txt md5sum readme* cafbb24f3dc7131501142f75deaeccbd readme.11.22.txt Download and install the binary files as discussed in the readme files. The binary files are available in the same directory as the readme files. MANUAL ACTIONS: Yes - NonUpdate 1. Set ip_pmtu_strategy=0 2. EITHER a. Filter out the following ICMP messages: Type 3, Code 2 (Destination Unreachable, Protocol Unreachable) Type 3, Code 3 (Destination Unreachable, Port Unreachable) Type 4, Code 0 (Source Quench) OR b. Install the appropriate binary file or patch. BULLETIN REVISION HISTORY: Revision 0: 25 May 2005 Initial release Revision 1: 1 June 2005 Binary files for B.11.00 and B.11.22 are available. Added information about CAN-2004-1060. The "set ip_pmtu_strategy=0" workaround is required even if binary files are installed. Removed IPSec information. Revision 2: 19 June 2005 TOUR (Transport Optional Upgrade Release) on B.11.11 and B.11.23 is potentially vulnerable. Added a description of the sequence number check implemented in the binary files. Revision 3: 27 June 2005 PHNE_33159 is available for B.11.11. The B.11.11 binary files have been removed from the ftp site. Revision 4: 10 July 2005 PHNE_32606 is available for B.11.23. The B.11.23 binary files have been removed from the ftp site. Revision 5: 24 July 2005 PHNE_33395 is available for B.11.00. The B.11.00 binary files have been removed from the ftp site. Added discussion of ip_pmtu_strategy=0. It is optional if patches are installed. Moved or deleted some text for readability. Revision 6: 15 August 2005 PHNE_33427 is available for B.11.04. Clarified the B.11.23 TOUR information. Modified ip_pmtu_strategy note. HP-UX SPECIFIC SECURITY BULLETINS*: Security Patch Check revision B.02.00 analyzes all HP-issued Security Bulletins to provide a subset of recommended actions that potentially affect a specific HP-UX system. For more information: http://www.software.hp.com/cgi-bin/swdepot_parser.cgi/cgi/ displayProductInfo.pl?productNumber=B6834AA SUPPORT: For further information, contact normal HP Services support channel. REPORT: To report a potential security vulnerability with any HP supported product, send Email to: email@example.com. It is strongly recommended that security related information being communicated to HP be encrypted using PGP, especially exploit information. To obtain the security-alert PGP key please send an e-mail message to firstname.lastname@example.org with the Subject of 'get key' (no quotes). SUBSCRIBE: To initiate a subscription to receive future HP Security Bulletins via Email: http://h30046.www3.hp.com/driverAlertProfile.php?regioncode=NA& langcode=USENG&jumpid=in_SC-GEN__driverITRC&topiccode=ITRC On the web page: ITRC security bulletins and patch sign-up Under Step1: your IRTC security bulletins and patches - check ALL categories for which alerts are required and continue. Under Step2: your IRTC operating systems - verify your operating system selections are checked and save. To update an existing subscription: http://h30046.www3.hp.com/subSignIn.php Log in on the web page Subscriber's choice for Business: sign-in. On the Web page: Subscriber's Choice: your profile summary - use Edit Profile to update appropriate sections. To review previously published Security Bulletins visit: http://itrc.hp.com/service/cki/secBullArchive.do * The Software Product Category that this Security Bulletin relates to is represented by the 5th and 6th characters of the Bulletin number: GN = HP General SW, MA = HP Management Agents, MI = Misc. 3rd party SW, MP = HP MPE/iX, NS = HP NonStop Servers, OV = HP OpenVMS, PI = HP Printing & Imaging, ST = HP Storage SW, TL = HP Trusted Linux, TU = HP Tru64 UNIX, UX = HP-UX, VV = HP Virtual Vault System management and security procedures must be reviewed frequently to maintain system integrity. HP is continually reviewing and enhancing the security features of software products to provide customers with current secure solutions. "HP is broadly distributing this Security Bulletin in order to bring to the attention of users of the affected HP products the important security information contained in this Bulletin. HP recommends that all users determine the applicability of this information to their individual situations and take appropriate action. HP does not warrant that this information is necessarily accurate or complete for all user situations and, consequently, HP will not be responsible for any damages resulting from user's use or disregard of the information provided in this Bulletin. To the extent permitted by law, HP disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose, title and non-infringement." (c)Copyright 2005 Hewlett-Packard Development Company, L.P. Hewlett-Packard Company shall not be liable for technical or editorial errors or omissions contained herein. The information provided is provided "as is" without warranty of any kind. To the extent permitted by law, neither HP nor its affiliates, subcontractors or suppliers will be liable for incidental, special or consequential damages including downtime cost; lost profits; damages relating to the procurement of substitute products or services; or damages for loss of data, or software restoration. The information in this document is subject to change without notice. Hewlett-Packard Company and the names of Hewlett-Packard products referenced herein are trademarks of Hewlett-Packard Company in the United States and other countries. Other product and company names mentioned herein may be trademarks of their respective owners. - -----BEGIN PGP SIGNATURE----- Version: PGP 8.1 iQA/AwUBQwHPBOAfOvwtKn1ZEQLO4gCff6+xLI00LPtPARsZdxLqBg67I0oAnRdc YlYyHQu0h+EG4Ej4lqbQzaZC =EKrT - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to email@example.com and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 If you believe that your computer system has been compromised or attacked in any way, we encourage you to let us know by completing the secure National IT Incident Reporting Form at: http://www.auscert.org.au/render.html?it=3192 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: firstname.lastname@example.org Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBQwPyTSh9+71yA2DNAQI7WgP/WS40h48YGdgKp59tZpzUK1Iuh7fPBOTp 4yJg16HJ83N03rpcws+08SDKRpzbkf3TQSt0yf97ZbP4sPRCGZpkzLHwD6Ia2NBV Wyx10uaROzocEfoFSANPqA84xe6q2K37nKlAUgBHzIqC1Ez09pmpPT16c87x+zyv R9TplpV1WnU= =UJ43 -----END PGP SIGNATURE-----