22 April 2008
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2008.0411 -- [UNIX][NetBSD] Integer overflow in strfmon(3) function 22 April 2008 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: libc Publisher: NetBSD Operating System: NetBSD UNIX specific Impact: Execute Arbitrary Code/Commands Delete Arbitrary Files Access: Remote/Unauthenticated CVE Names: CVE-2008-1391 Original Bulletin: ftp://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2008-006.txt.asc - --------------------------BEGIN INCLUDED TEXT-------------------- - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2008-006 ================================= Topic: Integer overflow in strfmon(3) function Version: NetBSD-current: affected NetBSD 4.0: affected NetBSD 3.1.*: unaffected NetBSD 3.1: unaffected NetBSD 3.0: unaffected NetBSD 3.0.*: unaffected Severity: Local user may be able to execute arbitrary code Fixed: NetBSD-current: March 18, 2008 NetBSD-4 branch: March 19, 2008 (4.1 will include the fix) NetBSD-4-0 branch: March 19, 2008 (4.0.1 will include the fix) Abstract ======== The strfmon() function contains multiple integer overflows which can be exploited by a local attacker to cause a crash or potentially execute arbitrary code. Technical Details ================= The vulnerability exists in strfmon() because of the use of the GET_NUMBER() macro. This macro does not check for integer overflow, and its value is passed as an argument to the memmove() and memset() functions, which can result in a crash or possibly the execution of arbitrary code. This issue has been assigned CVE reference CVE-2008-1391. Solutions and Workarounds ========================= The following instructions describe how to upgrade your libc binaries by updating your source tree and rebuilding and installing a new version of libc. * NetBSD-current: Systems running NetBSD-current dated from before 2008-03-18 should be upgraded to NetBSD-current dated 2008-03-19 or later. The following files need to be updated from the netbsd-current CVS branch (aka HEAD): lib/libc/stdlib/strfmon.c To update from CVS, re-build, and re-install libc: # cd src # cvs update lib/libc/stdlib/strfmon.c # cd lib/libc # make USETOOLS=no cleandir dependall # make USETOOLS=no install * NetBSD 4.*: Systems running NetBSD 4.* sources dated from before 2008-03-19 should be upgraded from NetBSD 4.* source dated 2008-03-20 or later. The following files need to be updated from the netbsd-4 or netbsd-4-0 CVS branches: lib/libc/stdlib/strfmon.c To update from CVS, re-build, and re-install libc: # cd src # cvs update -r <branch_name> lib/libc/stdlib/strfmon.c # cd lib/libc # make USETOOLS=no cleandir dependall # make USETOOLS=no install Thanks To ========= Maksymilian Arciemowicz for reporting this problem and Christos Zoulas for providing a fix. Revision History ================ 2008-04-21 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-SA2008-006.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/. Copyright 2008, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2008-006.txt,v 1.1 2008/04/15 20:19:56 adrianp Exp $ - -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (NetBSD) iQCVAwUBSAUSOD5Ru2/4N2IFAQLzCAQAp1P1sXgdVdcBYZ792JaU+ojWGMW3PqR1 tjSnp8rbkENkfGdtGKlkT2rLHshKiM0DzZL6SyiEDleSZtAv4cuzVQZf2ia+5WWR SI9TOo/WkPivXnwuKxW1XVefH00wv/KK5wsZAXNxWFY/oIs1pNWQ6QUi4umGmj8L C7he0Od/rdk= =2ESK - -----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 firstname.lastname@example.org and we will forward your request to the appropriate person. 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On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQCVAwUBSA1XOih9+71yA2DNAQJEuAP9FYNORZNj6hcj5Lu7S1uX8J4e/TJAMqsf ficTyUTWDpLaGN+s2KxeCD/5NwCPcC4zmM0VbuPP08G+rwVNEzyLHsKAA+D1l3T5 QvyVFNfOh9Ycjfwk1xCHW8sXdrMJ5LqSQwt2Te/tZ3qyagF9qTdJsLuP/C+SqXXs U5zS0SQAGyY= =afMK -----END PGP SIGNATURE-----