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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2009.0600 -- [NetBSD] proplib: Denial of Service 24 June 2009 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: proplib Publisher: NetBSD Operating System: NetBSD Impact: Denial of Service Access: Existing Account Original Bulletin: ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2009-003.txt.asc - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2009-003 ================================= Topic: proplib crashes on reading bad XML data Version: NetBSD-current: affected prior to March 30, 2009 NetBSD 5.0: not affected NetBSD 4.0.1: affected NetBSD 4.0: affected Severity: Denial of service Fixed: NetBSD-current: March 30, 2009 NetBSD-5 branch: March 30, 2009 (5.0 includes the fix) NetBSD-4-0 branch: March 31, 2009 (4.0.2 will include the fix) NetBSD-4 branch: March 31, 2009 (4.1 will include the fix) Please note that NetBSD releases prior to 4.0 are no longer supported. It is recommended that all users upgrade to a supported release. Abstract ======== The proplib library can crash if a badly formatted externalized plist is presented for import. The crash will happen during the transformation of the text XML form into a binary list. This bug can lead to a system panic because many drivers use proplib as a communication channel. Technical Details ================= The proplib library can crash if it is presented with a non-defined element (e.g. <number>) in the external XML form. During internalization proplib will crash by dereferencing a NULL pointer. Every driver which uses proplib for user to kernel communication is vulnerable to this bug, allowing a system to be crashed by an ordinary user with access to the driver. Solutions and Workarounds ========================= For all NetBSD versions, you need to obtain fixed sources, rebuild and install a new kernel, and reboot the system. The fixed source may be obtained from the NetBSD CVS repository. The following instructions briefly summarize how to upgrade your kernel. In these instructions, replace: ARCH with your architecture (from uname -m), and KERNCONF with the name of your kernel configuration file. To update from CVS, re-build, and re-install the kernel: # cd src # cvs update -d -P common/lib/libprop/prop_object.c # ./build.sh kernel=KERNCONF # mv /netbsd /netbsd.old # cp sys/arch/ARCH/compile/obj/KERNCONF/netbsd /netbsd # shutdown -r now For more information on how to do this, see: http://www.NetBSD.org/guide/en/chap-kernel.html Recompiling and reinstalling the userlevel libprop (located in src/lib/libprop) may be prudent to prevent unexpected crashes of userland code, but should not be necessary for security purposes. In order to recompile and reinstall your userlevel libprop: # cd src/lib/libprop # make USETOOLS=no cleandir dependall # make USETOOLS=no install Thanks To ========= Adam Hamsik for the fix and initial analysis of the issue and for the first draft of this advisory, and to Soren Jacobsen and David Holland for assistance with the content of this advisory. Revision History ================ 2009-06-22 Initial release More Information ================ Advisories may be updated as new information becomes available. The most recent version of this advisory (PGP signed) can be found at ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2009-003.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/. Copyright 2009, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2009-003.txt,v 1.1 2009/06/22 19:31:01 tonnerre Exp $ - -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (NetBSD) iQCVAwUBSj/8RT5Ru2/4N2IFAQJdvgP/edYmzjp0DlDjo6glc6w8K9diUQQ+92SG 5U42Kmf/hRxnHn0hZLXB7txLSWfks9DFiTVfGWyBXKFtS9h05YfWCjP1flwxvviN Uv8y8iDB/krAq9lR9M0x3CMlpe7Hfzpje04fXRLxUloLA427EWGCXA2noyNhPpnu OKn8ivX4VUs= =setc - -----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 auscert@auscert.org.au and we will forward your request to the appropriate person. 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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: auscert@auscert.org.au 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 iD8DBQFKQWlVNVH5XJJInbgRAvCyAJ43c1dvGj4sOl5AlmAGM8924ODOswCeNg21 RXGcxSplZtIA0Z18lS2yN8s= =UaLZ -----END PGP SIGNATURE-----