30 March 2007
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2007.0204 -- [NetBSD] Insufficient length checking in iso(4) 30 March 2007 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: iso Publisher: NetBSD Operating System: NetBSD Impact: Root Compromise Access: Existing Account CVE Names: CVE-2007-1677 Original Bulletin: ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2007-004.txt.asc - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2007-004 ================================= Topic: Insufficient length checking in iso(4) Version: NetBSD-current: source prior to March 29, 2007 NetBSD 4.0_BETA2: affected NetBSD 3.1: affected NetBSD 3.0.*: affected NetBSD 3.0: affected NetBSD 2.1: affected NetBSD 2.0.*: affected NetBSD 2.0: affected Severity: Local denial of service, Local root compromise Fixed: NetBSD-current: March 29, 2007 NetBSD-4 branch: March 29, 2007 NetBSD-3-1 branch: March 29, 2007 NetBSD-3-0 branch: March 29, 2007 NetBSD-3 branch: March 29, 2007 NetBSD-2-1 branch: March 29, 2007 NetBSD-2-0 branch: March 29, 2007 NetBSD-2 branch: March 29, 2007 Abstract ======== Due to insufficient length checking in iso(4) it is possible for a local user to cause an overflow, resulting in a local denial of service or local root compromise. This vulnerability has been assigned CVE reference CVE-2007-1677. Technical Details ================= A number of functions in the iso(4) code including clnp_route() do not validate the length of arguments passed. As a result of this a user could supply a bad 'sockaddr' structure to clnp_route() via connect(2). This can lead to a root compromise if exploited correctly or a denial of service (panic). Solutions and Workarounds ========================= Kernels with the ISO protocol family support are affected, including the default GENERIC kernel install. Users of affected NetBSD versions are highly recommended to upgrade their kernel. Only kernels compiled with the following option are vulnerable to this issue: options ISO As a temporary workaround recompile the kernel with the above option commented out. For all NetBSD versions, you need to obtain fixed kernel sources, rebuild and install the new kernel, and reboot the system. The fixed source may be obtained from the NetBSD CVS repository. The following instructions briefly summarise 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 sys/netiso/clnp_subr.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 Thanks To ========= Christer Oberg of BitSec discovered and reported this issue. Christos Zoulas fixed the code. Revision History ================ 2007-03-29 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-SA2007-004.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/. Copyright 2007, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2007-004.txt,v 1.1 2007/03/29 08:21:51 adrianp Exp $ - -----BEGIN PGP SIGNATURE----- iQCVAwUBRgt3bD5Ru2/4N2IFAQIUCgP8CFUfPmY1UC7w8Igr1MUJZggbhjJqjU0J zWl0gfFgc8iWZ2arXnyj6+pNKKUNNrWt9y4VVPjfF7pFDdhpiERt6vei489fU3xF 0PeU4DzKqvVp/eEmwieLzWMwDCXsfy5JUdAKMWJHEcqn4DOuVTzYfKjG3Zma4edp tBzmCuTHuPM= =efD4 - -----END PGP SIGNATURE----- - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. 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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 iQCVAwUBRgyFuSh9+71yA2DNAQLinQP/Z1TbRms3JZb1ZMA3wMYaGPXRTfyC+0X8 d+DSOEdudwdJ6fv6AN/TQD3ujjGP1chdLgfQGO8OCoYy9r/bDcp3kNZ0h+7KOSp8 dWO7xZj+kffrtsEfbhdhYgTP3ZZgJCkHkCPWLlwOkjoSxRLdbMYbTWObvRFWUIlT kEjl3t4PaOQ= =351B -----END PGP SIGNATURE-----