/usr/share/mibs/ is in libsnmp-base 5.4.3~dfsg-2.8+deb7u1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/mibs/netsnmp/
/usr/share/mibs/netsnmp/GNOME-SMI
/usr/share/mibs/netsnmp/LM-SENSORS-MIB
/usr/share/mibs/netsnmp/NET-SNMP-AGENT-MIB
/usr/share/mibs/netsnmp/NET-SNMP-EXAMPLES-MIB
/usr/share/mibs/netsnmp/NET-SNMP-EXTEND-MIB
/usr/share/mibs/netsnmp/NET-SNMP-MIB
/usr/share/mibs/netsnmp/NET-SNMP-MONITOR-MIB
/usr/share/mibs/netsnmp/NET-SNMP-PASS-MIB
/usr/share/mibs/netsnmp/NET-SNMP-SYSTEM-MIB
/usr/share/mibs/netsnmp/NET-SNMP-TC
/usr/share/mibs/netsnmp/NET-SNMP-VACM-MIB
/usr/share/mibs/netsnmp/UCD-DEMO-MIB
/usr/share/mibs/netsnmp/UCD-DISKIO-MIB
/usr/share/mibs/netsnmp/UCD-DLMOD-MIB
/usr/share/mibs/netsnmp/UCD-IPFWACC-MIB
/usr/share/mibs/netsnmp/UCD-SNMP-MIB