Description

Detects insecure SNMP connections in Python code using the pysnmp library. SNMP provides remote management capabilities for network devices, and using it without proper security controls can expose sensitive system information or allow unauthorized access.

Detection Strategy

• Check if the pysnmp library is imported in the Python code

• Look for usage of specific SNMP-related classes that are known to be insecure by default

• Report a vulnerability when these dangerous SNMP classes are instantiated or used without proper security configurations

Vulnerable code example

from pysnmp.hlapi import CommunityData, SnmpEngine, UdpTransportTarget, getCmd, ObjectType, ObjectIdentity

# VULNERABLE: Uses SNMPv2c with cleartext community string
iterator = getCmd(
    SnmpEngine(),
    CommunityData("public"),  # Transmits community string in cleartext
    UdpTransportTarget(("router.example.com", 161)),
    ObjectType(ObjectIdentity("SNMPv2-MIB", "sysDescr", 0))...

✅ Secure code example

from pysnmp.hlapi import (
    ObjectIdentity,
    ObjectType,
    SnmpEngine,
    UdpTransportTarget,
    UsmUserData,
    getCmd,
    usmAesCfb128Protocol,  # AES is more secure than DES...