The vos command in OpenAFS 1.6.x before 1.6.5, when using the -encrypt option, only enables integrity protection and sends data in cleartext, which allows remote attackers to obtain sensitive information by sniffing the network.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2013-4063
http://www.openafs.org/pages/security/OPENAFS-SA-2013-004.txt
http://www.mandriva.com/security/advisories?name=MDVSA-2014:244