FreeRADIUS before 1.0.1 allows remote attackers to cause a denial of service (core dump) via malformed USR vendor-specific attributes (VSA) that cause a memcpy operation with a -1 argument.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11023
https://exchange.xforce.ibmcloud.com/vulnerabilities/17440
http://www.securityfocus.com/bid/11222