Cisco Secure Firewall - SSH Connection to sshd_operns
This analytic detects inbound SSH connections to the sshd_operns service on network devices using Cisco Secure Firewall Intrusion Events. APT actors have been observed enabling sshd_operns and opening it on…
Description
This analytic detects inbound SSH connections to the sshd_operns service on network devices using Cisco Secure Firewall Intrusion Events. APT actors have been observed enabling sshd_operns and opening it on non-standard ports to maintain encrypted remote access to compromised network infrastructure. This detection leverages Snort signature 65368 to identify connections to this service, which when combined with other indicators may signal persistent access mechanisms established by threat actors.
Detection logic
Detection requirements
- Platform
- ESXiLinuxmacOS
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- cisco_secure_firewall_threat_defense_intrusion_event
Known benign triggers
- No false positives have been identified yet.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.cisa.gov/news-events/cybersecurity-advisories/aa25-239a | 14 |
From the source
- At source
- Open at source
- Upstream identifier
- 8a9c1d2e-3f4b-5c6d-7e8f-9a0b1c2d3e4f
- Tagged by the source as
- Cisco Secure Firewall Threat Defense AnalyticsSalt TyphoonNetworknetworkSplunk CloudSplunk EnterpriseSplunk Enterprise Securitynetwork
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1