Improving the Security and Reliability of the SNMP protocol

What is SNMP ?

The SNMP protocol - Simple Network Management Protocol , is a networking protocol allowing network administrators to manage network equipments and perform diagnostics on networking issues.

How does it work?

It has 2 main parts: A supervisor and an agent. The Supervisor is the console that allows the network admin to execute management requests. Agents are network entities at interface level that connect the managed equipment to the network allowing us to get information on different objects.

Equipments

Switches, hubs, routers and servers are all manageable by SNMP.

Issues/Vulnerability

The issues with those network equipment is as we're trying to make them smaller and compact, we have some CPU and memory issues to consider. Most consumer routers have around 8-32 MB of RAM.

In case memory is wrongly allocated, and/or the amount of memory allocated is not checked, this can allow a denial of service (memory consumption or daemon crash) or memory leaks

Example:

denial of service due to unchecked malloc in client authentication

CVE-2014-8091: In servers built with support for SUN-DES-1 (Secure RPC) authentication credentials, an unauthenticated client may be able to crash the X server by sending a connection request specifying values that cause malloc to fail, causing the authentication routines to attempt to write data to the returned NULL pointer. Since the request is limited to an unsigned 16-bit integer for the allocation size, it is unlikely to fail unless the server is severely memory constrained.
Introduced in the initial revision of Secure RPC support in X11R5 (1991).

Companies that use it:

HP, Fujitsu, Dell, IBM, CISCO

Fix

See my fix at the following link:

https://sourceforge.net/u/devildron/net-snmp/ci/e30a927350c0cba19750cd9fb67db175933973d6/