This joint advisory from multiple national cybersecurity agencies reports that Russian FSB Center 16 actors are actively scanning for and exploiting poorly configured network devices (notably routers) using SNMP v1/v2 community strings and occasional CVE-based exploits to copy device configurations and exfiltrate them via TFTP/FTP to actor-controlled infrastructure; the advisory maps observed behavior to MITRE ATT&CK, lists affected critical infrastructure sectors, provides example OIDs/IOCs, and gives prioritized mitigations (use SNMPv3, disable Cisco Smart Install, block TFTP/SNMP/SMI at edges, enforce strong credentials, and update device firmware).