CVE 2005-3806
The IPv6 flow label handling code (ip6_flowlabel.c) in Linux kernels 2.4 up to 2.4.32 and 2.6 before 2.6.14 modifies the wrong variable in certain circumstances, which allows local users to corrupt kernel memory or cause a denial of service (crash) by triggering a free of non-allocated memory.
See the
CVE page on Mitre.org
for more details.