Michael MIC Failure Report with RSN?

[Helmut Schaa]

Hi,

I've got a client connected to hostapd that is sending a Michael MIC
Failure Report to
a RSN-only AP after the group key handshake:

hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key frame (2/2 Group)
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: group key handshake completed (RSN)

hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key frame (Request)
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key Error
Request (STA detected Michael MIC failure)

hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: sending 1/4 msg of 4-Way Handshake
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key frame
(2/4 Pairwise)
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: sending 3/4 msg of 4-Way Handshake
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key frame
(4/4 Pairwise)
hostapd: wlan0: STA 00:40:8c:xx:xx:xx IEEE 802.1X: authorizing port
hostapd: wlan0: STA 00:40:8c:xx:xx:xx RADIUS: starting accounting
session 4E54C35C-00000009
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: pairwise key handshake
completed (RSN)

hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key frame (Request)
hostapd: wlan0: STA 00:40:8c:xx:xx:xx WPA: received EAPOL-Key Error
Request (STA detected Michael MIC failure)

hostapd: wlan0: IEEE 802.11 TKIP countermeasures initiated

I don't have access to this client but is it really necessary to start
TKIP countermeasures
when running in RSN-only mode (which will deauth all associated clients)?

Thanks,
Helmut