The cfg80211_wext_giwessid function in net/wireless/wext-compat.c in the Linux kernel before 2.6.36-rc3-next-20100831 does not properly initialize certain structure members, which allows local users to leverage an off-by-one error in the ioctl_standard_iw_point function in net/wireless/wext-core.c, and obtain potentially sensitive information from kernel heap memory, via vectors involving an SIOCGIWESSID ioctl call that specifies a large buffer size.
forums.grsecurity.net/viewtopic.php?f=3&t=2290
git.kernel.org/?p=linux/kernel/git/linville/wireless-2.6.git%3Ba=commit%3Bh=42da2f948d949efd0111309f5827bf0298bcc9a4
grsecurity.net/~spender/wireless-infoleak-fix2.patch
lists.opensuse.org/opensuse-security-announce/2010-11/msg00000.html
lists.opensuse.org/opensuse-security-announce/2011-02/msg00000.html
lkml.org/lkml/2010/8/27/413
lkml.org/lkml/2010/8/30/127
lkml.org/lkml/2010/8/30/146
lkml.org/lkml/2010/8/30/351
secunia.com/advisories/41245
www.kernel.org/pub/linux/kernel/v2.6/next/patch-v2.6.36-rc3-next-20100831.bz2
www.openwall.com/lists/oss-security/2010/08/31/1
www.redhat.com/support/errata/RHSA-2010-0771.html
www.redhat.com/support/errata/RHSA-2010-0842.html
www.securityfocus.com/bid/42885
www.ubuntu.com/usn/USN-1000-1
www.vupen.com/english/advisories/2011/0298
bugzilla.redhat.com/show_bug.cgi?id=628434