Integer overflow in the __tzfile_read function in glibc before 2.15 allows context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted timezone (TZ) file, as demonstrated using vsftpd.
https://bugzilla.redhat.com/show_bug.cgi?id=761245
http://sourceware.org/git/?p=glibc.git%3Ba=commit%3Bh=97ac2654b2d831acaa18a2b018b0736245903fd2
http://lists.grok.org.uk/pipermail/full-disclosure/2011-December/084452.html