A vulnerability was found in how hostapd and wpa_supplicant writes the configuration file update for the WPA/WPA2 passphrase parameter. If this parameter has been updated to include control characters either through a WPS operation or through local configuration change over the wpa_supplicant control interface, the resulting configuration file may prevent the hostapd and wpa_supplicant from starting when the updated file is used.
A vulnerability was found in how hostapd and wpa_supplicant writes the configuration file update for the WPA/WPA2 passphrase parameter. If this parameter has been updated to include control characters either through a WPS operation or through local configuration change over the wpa_supplicant control interface, the resulting configuration file may prevent the hostapd and wpa_supplicant from starting when the updated file is used.
http://www.openwall.com/lists/oss-security/2016/05/03/2