CVE-2009-2844

cfg80211 in net/wireless/scan.c in the Linux kernel 2.6.30-rc1 and other
versions before 2.6.31-rc6 allows remote attackers to cause a denial of
service (crash) via a sequence of beacon frames in which one frame omits an
SSID Information Element (IE) and the subsequent frame contains an SSID IE,
which triggers a NULL pointer dereference in the cmp_ies function. NOTE: a
potential weakness in the is_mesh function was also addressed, but the
relevant condition did not exist in the code, so it is not a vulnerability.