SMNP is used to manage and monitor all sorts of equipment including computers, core router switches, broadband devices, printers, and sniffers. The protocol works by sending Protocol Data Units (PDUs) to different parts of the network. Agents, devices which are made SNMP-compliant devices, store data about themselves in Management Information Bases (MIBs) and return this data to the SNMP requesters.
SNMP supports five different types of messages:
There has been some discussion on what network managers should do, given that several major brands of firewalls utilize SNMP, and may therefore be vulnerable themselves, but prudence would seem to dictate that until the appropriate patches are applied, those ports which use SNMP should be shut down for the nonce.https://o1.qnsr.com/log/p.gif?;n=203;c=204660766;s=9477;x=7936;f=201812281312070;u=j;z=TIMESTAMP;a=20392931;e=iCERT has published a vendor-by-vendor listing, determining whether or not their implementation is vulnerable, and the date of their latest patch. Now that the cat is out of the bag, and those who would break into systems are aware of these flaws, it is paramount that network managers update to these patches ASAP.
Double-check that your firewalls are filtering out unauthorized SNMP data traffic, and you may consider disabling equipment that uses SNMP services for which patches are not yet available.
This article was first published on CrossNodes, an internet.com site.