-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 NetBSD Security Advisory 2014-005 ================================= Topic: libXfont multiple vulnerabilities Version: NetBSD-current: source prior to May 13th, 2014 NetBSD 6.1 - 6.1.4: affected NetBSD 6.0 - 6.0.5: affected NetBSD 5.1 - 5.1.4: affected NetBSD 5.2 - 5.2.2: affected Severity: privilege escalation Fixed: NetBSD-current: May 13th, 2014 NetBSD-6-0 branch: May 14th, 2014 NetBSD-6-1 branch: May 14th, 2014 NetBSD-6 branch: May 14th, 2014 NetBSD-5-2 branch: May 14th, 2014 NetBSD-5-1 branch: May 14th, 2014 NetBSD-5 branch: May 14th, 2014 Teeny versions released later than the fix date will contain the fix. Please note that NetBSD releases prior to 5.1 are no longer supported. It is recommended that all users upgrade to a supported release. Abstract ======== integer overflow of allocations in font metadata file parsing This vulnerability has been assigned CVE-2014-0209 unvalidated length fields when parsing xfs protocol replies This vulnerability has been assigned CVE-2014-0210 integer overflows calculating memory needs for xfs replies This vulnerability has been assigned CVE-2014-0211 The X server commonly runs as root; the user using the X server controls the fontpath. A malicious local user could thus utilize buffer overflows via setting the fontpath to a prepared font directory, or to a malicious xfs server to execute code as root. Technical Details ================= citing from the X.org advisory: integer overflow of allocations in font metadata file parsing When a local user who is already authenticated to the X server adds a new directory to the font path, the X server calls libXfont to open the fonts.dir and fonts.alias files in that directory and add entries to the font tables for every line in it. A large file (~2-4 gb) could cause the allocations to overflow, and allow the remaining data read from the file to overwrite other memory in the heap. unvalidated length fields when parsing xfs protocol replies When parsing replies received from the font server, these calls do not check that the lengths and/or indexes returned by the font server are within the size of the reply or the bounds of the memory allocated to store the data, so could write past the bounds of allocated memory when storing the returned data. integer overflows calculating memory needs for xfs replies These calls do not check that their calculations for how much memory is needed to handle the returned data have not overflowed, so can result in allocating too little memory and then writing the returned data past the end of the allocated buffer. Solutions and Workarounds ========================= Update libXfont to a non-vulnerable version. libXfont is contained in xbase.tgz, so get http://nyftp.netbsd.org/pub/NetBSD-daily////binary/sets/xbase.tgz with =release, =date > 20140514, =arch (for example: http://nyftp.netbsd.org/pub/NetBSD-daily/netbsd-6/201405220640Z/amd64/binary/sets/xbase.tgz) and then: for X.org cd / ; tar xzpf xbase.tgz ./usr/X11R7/lib/libXfont.so.3.0 for xfree cd / ; tar xzpf xbase.tgz ./usr/X11R6/lib/libXfont.so.1.5 or rebuild the system from fixed source with build.sh -x Fixed versions: X.org: xsrc/external/mit/libXfont/dist/src/ HEAD 6 6-1 6-0 fc/fsconvert.c 1.2 1.1.1.2.2.1 1.1.1.2.6.1 1.1.1.2.4.1 fc/fserve.c 1.2 1.1.1.2.2.1 1.1.1.2.6.1 1.1.1.2.4.1 fontfile/dirfile.c 1.2 1.1.1.2.2.1 1.1.1.2.6.1 1.1.1.2.4.1 5 5-2 5-1 fc/fsconvert.c 1.1.1.1.2.2 1.1.1.1.2.1.4.1 1.1.1.1.2.1.2.1 fc/fserve.c 1.1.1.1.2.2 1.1.1.1.2.1.4.1 1.1.1.1.2.1.2.1 fontfile/dirfile.c 1.1.1.1.2.2 1.1.1.1.2.1.4.1 1.1.1.1.2.1.2.1 xfree: xsrc/xfree/xc/lib/font/ HEAD 6 6-1 6-0 fc/fsconvert.c 1.5 1.4.26.1 1.4.32.1 1.4.28.1 fc/fserve.c 1.5 1.4.26.1 1.4.32.1 1.4.28.1 fontfile/dirfile.c 1.5 1.4.14.1 1.4.20.1 1.4.16.1 5 5-2 5-1 fc/fsconvert.c 1.4.20.1 1.4.30.1 1.4.24.1 fc/fserve.c 1.4.20.1 1.4.30.1 1.4.24.1 fontfile/dirfile.c 1.4.8.1 1.4.18.1 1.4.12.1 Thanks To ========= Thanks to Ilja van Sprundel, a security researcher with IOActive, who discovered the issues and the X.org security team for developing fixes and coordinating the vulnerability release. Revision History ================ 2014-05-28 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 http://ftp.NetBSD.org/pub/NetBSD/security/advisories/NetBSD-SA2014-005.txt.asc Information about NetBSD and NetBSD security can be found at http://www.NetBSD.org/ and http://www.NetBSD.org/Security/ . Copyright 2014, The NetBSD Foundation, Inc. All Rights Reserved. Redistribution permitted only in full, unmodified form. $NetBSD: NetBSD-SA2014-005.txt,v 1.1 2014/05/27 23:53:20 tonnerre Exp $ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJThSWUAAoJEAZJc6xMSnBu4Y4P/jdaNc5mGuFIWhReYrraP2Dd Mo3ppm1BsMBHjaDKe8ldM7ggIwO8kswi8HWtpR4z2tPwuoYPFi9nDKpOJLNscsbR PwOSmnd7DRxOWYL4t6IiS4S8N0tsuN6gaOduWB/3KMASuvEGi7MOAe+k+24JT8oa jj9/IDNv/6XfoWHPTxN2uUAYAV278WmQpMIVt40mISrGXighTQ7wUDz90GnBT7Vq jt6ZdtjdB8k95/0OoFruRZkLmXOVjNmdsjcPw1dbxiM2J5otB2G1chxXCdEF+I2a NB4L1eqUG4+xDd3oemlDpqmfkxMwdOfjDTuiPD2LqHjlokt+EK15T7tWtfD5IZCx 8jNjHbjrK8L7Zp6Wa9VdcLmFJVc3cNLlUxJZATVA7kK9du25GDXBiBKd7P57NJOw eBZo8Ku+fMph7B409Ii2+tTubmTUWAX4raoIXhcrLGz+NtEFPB072gnpCkhVw6bR hZ2ZR9o2Xb3+bdLjGqTEjJCJLRFfYn4r3fVA/cdLPlSC6mtZ9fbKScsIOmZooo1Z L+Z36Cv3j6CrDSgDqmmabrC/atXQ9cK7Wzntu/DRKfq8vkPuSMlpuQRlfzjcgSsH /nGY+0AG10/QVOncgK+zS/a536zrPfQynTGgx+rluClxIzWUYzDRZt00C8/I41wJ eP+z29hbJ2KmuDl8QIvK =VDy0 -----END PGP SIGNATURE-----