FreeBSD: VID-bc19dcca-7b13-11e6-b99e-589cfc0654e1 (CVE-2016-7408): dropbear -- multiple vulnerabilities

Matt Johnston reports: If specific usernames including "%" symbols can be created on a system (validated by getpwnam()) then an attacker could run arbitrary code as root when connecting to Dropbear server. A dbclient user who can control username or host arguments could potentially run arbitrary code as the dbclient user. This could be a problem if scripts or webpages pass untrusted input to the dbclient program. dropbearconvert import of OpenSSH keys could run arbitrary code as the local dropbearconvert user when parsing malicious key files. dbclient could run arbitrary code as the local dbclient user if particular -m or -c arguments are provided. This could be an issue where dbclient is used in scripts. dbclient or dropbear server could expose process memory to the running user if compiled with DEBUG_TRACE and running with -v