Software Engineering Institute

CWE-257: Storing Passwords in a Recoverable Format

For all Hirschmann (part of Belden) "Classic Platform" switches (which includes the MACH series workgroup switches, among others), by default, the switch administrator password is used to construct an SNMP community string that allows remote management of some switch configuration. Attackers on the local network with the ability to sniff network traffic may be able to recover the administrator password from the community string.

Belden has released security advisory BSECV-2016-2 which describes this issue in more detail.

An attacker on the local network may learn the switch administrator password from the SNMP community string, which is sent over the network in plaintext in SNMPv1 and SNMPv2.

Disable the SNMP Password Sync feature and use SNMPv3

Affected users may disable the password sync feature on their devices. For more information, please see Belden security advisory BSECV-2016-2. Users are also encouraged to use SNMPv3, which supports encrypted network traffic.

According to Hirschmann, the password sync feature was enabled by default to aid in network setup during the transition from SNMPv1/v2 to SNMPv3. Hirschmann has committed to disabling the password sync feature by default in future devices and firmware now that SNMPv3 is the default on their products.