Published:
21 January 1998
Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-98.012 -- Hewlett-Packard Security Bulletin: #00076 Security Vulnerability with land on HP-UX 22 January 1998 =========================================================================== Hewlett-Packard has released the following advisory concerning their susceptibility to the land attack. This vulnerability may allow users on the network to cause system hangs. The following security bulletin is provided as a service to AUSCERT's members. As AUSCERT did not write this document, AUSCERT has had no control over its content. As such, the decision to use any or all of this information is the responsibility of each user or organisation, and should be done so in accordance with site policies and procedures. NOTE: This is only the original release of the security bulletin. It will not be updated when the original bulletin is. If downloading at a later date, it is recommended that the bulletin is retrieved from the original authors to ensure that the information is still current. Contact information for HP is included in the Security Bulletin below. 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/Information/advisories.html If you believe that your system has been compromised, contact AUSCERT or your representative in FIRST (Forum of Incident Response and Security Teams). Internet Email: auscert@auscert.org.au 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 emergencies. Facsimile: (07) 3365 7031 - --------------------------BEGIN INCLUDED TEXT-------------------- - ------------------------------------------------------------------------- HEWLETT-PACKARD SECURITY BULLETIN: #00076, 21 January 1998 - ------------------------------------------------------------------------- The information in the following Security Bulletin should be acted upon as soon as possible. Hewlett-Packard will not be liable for any consequences to any customer resulting from customer's failure to fully implement instructions in this Security Bulletin as soon as possible. - ------------------------------------------------------------------------- PROBLEM: A TCP SYN packet with target host's address as both source and destination can cause system hangs. PLATFORM: HP9000 Series 7/800 running HP-UX releases 9.X, 10.X, and 11.00. DAMAGE: Users on the network can cause system hangs. SOLUTION: Apply patches listed below. AVAILABILITY: All patches are available now. - ------------------------------------------------------------------------- I. A. Background CERT Advisory CA-97.28 discusses the widely available "land" program, a denial of service tool that is effective against HP-UX systems. land sends carefully crafted TCP packets (the source and destination are identical). B. Fixing the problem The problem can be fixed by applying the appropriate cumulative ARPA Transport patch mentioned below. HP-UX release 11.00 HP9000 Series 700/800 PHNE_13692 HP-UX release 10.30 HP9000 Series 700/800 PHNE_13671 HP-UX release 10.20 HP9000 Series 800 PHNE_13468 HP-UX release 10.20 HP9000 Series 700 PHNE_13469 HP-UX release 10.10 HP9000 Series 800 PHNE_13470 HP-UX release 10.10 HP9000 Series 700 PHNE_13471 HP-UX release 10.01 HP9000 Series 800 PHNE_13472 HP-UX release 10.01 HP9000 Series 700 PHNE_13473 HP-UX release 10.00 HP9000 Series 800 PHNE_13474 HP-UX release 10.00 HP9000 Series 700 PHNE_13475 HP-UX release 9.04 HP9000 Series 800 PHNE_13476 HP-UX release 9.0[3,5,7] HP9000 Series 700 PHNE_13477 HP-UX release 9.01 HP9000 Series 700 PHNE_13478 HP-UX release 9.00 HP9000 Series 800 PHNE_13479 C. Impact of the patch The patch changes the implementation of the ISO OSI stack such that the host now enforces the rule that inbound packets are never from itself - if packets claim otherwise, they are simply dropped. D. To subscribe to automatically receive future NEW HP Security Bulletins from the HP Electronic Support Center via electronic mail, do the following: User your browser to get to the HP Electronic Support Center page at: http://us-support.external.hp.com (for US, Canada, Asia-Pacific, & Latin-America) http://europe-support.external.hp.com (for Europe) Click on the Technical Knowledge Database, register as a user (remember to save the User ID assigned to you, and your password), and it will connect to a HP Search Technical Knowledge DB page. Near the bottom is a hyperlink to our Security Bulletin archive. Once in the archive there is another link to our current security patch matrix. Updated daily, this matrix is categorized by platform/OS release, and by bulletin topic. F. To report new security vulnerabilities, send email to security-alert@hp.com Please encrypt any exploit information using the security-alert PGP key, available from your local key server, or by sending a message with a -subject- (not body) of 'get key' (no quotes) to security-alert@hp.com. Permission is granted for copying and circulating this Bulletin to Hewlett-Packard (HP) customers (or the Internet community) for the purpose of alerting them to problems, if and only if, the Bulletin is not edited or changed in any way, is attributed to HP, and provided such reproduction and/or distribution is performed for non-commercial purposes. Any other use of this information is prohibited. HP is not liable for any misuse of this information by any third party. ________________________________________________________________________ - -----End of Document ID: HPSBUX9801-076-------------------------------------- - --------------------------END INCLUDED TEXT-------------------- -----BEGIN PGP SIGNATURE----- Version: 2.6.3i Charset: noconv Comment: ftp://ftp.auscert.org.au/pub/auscert/AUSCERT_PGP.key iQCVAwUBNMcNLih9+71yA2DNAQHlagP+LQebAhU9c6ZHfD4DnJIMwXnXM97FKZ4A 93mKads88iVGlKyGGxnnXYw2MxaGqoEnZykKasU6+5j2KVbUFXLL49tjOp7PXQhY C61l+V4BOcvNTKTC3b1rnd43LB2EErQRaluMOaRr8m2hoTJbv9TFL/R9N/gVIXtk z8kQ9CiMtRA= =U6G6 -----END PGP SIGNATURE-----