Skip to content

Cisco IOS

Overview

Cisco IOS is a network operating system for Cisco ASR routers and Cisco Catalyst switches.

The following Sekoia.io built-in rules match the intake Cisco IOS router and switch. This documentation is updated automatically and is based solely on the fields used by the intake which are checked against our rules. This means that some rules will be listed but might not be relevant with the intake.

SEKOIA.IO x Cisco IOS router and switch on ATT&CK Navigator

Account Added To A Security Enabled Group

Detection in order to investigate who has added a specific Domain User in Domain Admins or Group Policy Creator Owners (Security event 4728)

  • Effort: master
Account Removed From A Security Enabled Group

Detection in order to investigate who has removed a specific Domain User in Domain Admins or Group Policy Creator Owners (Security event 4729)

  • Effort: master
Computer Account Deleted

Detects computer account deletion.

  • Effort: master
Cryptomining

Detection of domain names potentially related to cryptomining activities.

  • Effort: master
Domain Trust Created Or Removed

A trust was created or removed to a domain. An attacker could perform that in order to do lateral movement easily between domains or shutdown the ability of two domains to communicate.

  • Effort: advanced
Dynamic DNS Contacted

Detect communication with dynamic dns domain. This kind of domain is often used by attackers. This rule can trigger false positive in non-controlled environment because dynamic dns is not always malicious.

  • Effort: master
Exfiltration Domain

Detects traffic toward a domain flagged as a possible exfiltration vector.

  • Effort: master
Failed Logon Source From Public IP Addresses

A login from a public IP can indicate a misconfigured firewall or network boundary. The sekoia.tags are used to filter internal Ipv4 addresses (10.0.0.0/8 172.16.0.0/12 127.0.0.0/8 169.254.0.0/16 192.168.0.0/16).

  • Effort: master
Password Change On Directory Service Restore Mode (DSRM) Account

The Directory Service Restore Mode (DSRM) account is a local administrator account on Domain Controllers. Attackers may change the password to gain persistence.

  • Effort: intermediate
Possible Replay Attack

This event can be a sign of Kerberos replay attack or, among other things, network device configuration or routing problems.

  • Effort: intermediate
Remote Access Tool Domain

Detects traffic toward a domain flagged as a Remote Administration Tool (RAT).

  • Effort: master
SEKOIA.IO Intelligence Feed

Detect threats based on indicators of compromise (IOCs) collected by SEKOIA's Threat and Detection Research team.

  • Effort: elementary
Sekoia.io EICAR Detection

Detects observables in Sekoia.io CTI tagged as EICAR, which are fake samples meant to test detection.

  • Effort: master
TOR Usage Generic Rule

Detects TOR usage globally, whether the IP is a destination or source. TOR is short for The Onion Router, and it gets its name from how it works. TOR intercepts the network traffic from one or more apps on user’s computer, usually the user web browser, and shuffles it through a number of randomly-chosen computers before passing it on to its destination. This disguises user location, and makes it harder for servers to pick him/her out on repeat visits, or to tie together separate visits to different sites, this making tracking and surveillance more difficult. Before a network packet starts its journey, user’s computer chooses a random list of relays and repeatedly encrypts the data in multiple layers, like an onion. Each relay knows only enough to strip off the outermost layer of encryption, before passing what’s left on to the next relay in the list.

  • Effort: master
User Account Created

Detects user creation on windows servers, which shouldn't happen in an Active Directory environment. Apply this on your windows server logs and not on your DC logs. One default account defaultuser0 is excluded as only used during Windows set-up. This detection use Security Event ID 4720.

  • Effort: master
User Account Deleted

Detects local user deletion

  • Effort: master

Event Categories

The following table lists the data source offered by this integration.

Data Source Description
Host network interface every packets are logged and information on the outcome, the source/destination are extracted
Network device logs ACL logs are examined in detail
Network protocol analysis packets are fully analyzed

In details, the following table denotes the type of events produced by this integration.

Name Values
Kind ``
Category host
Type ``

Event Samples

Find below few samples of events and how they are normalized by Sekoia.io.

{
    "message": "FE03.LOCAL: Mar 6 2023 08:04:45.866 CET: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/13, changed state to down",
    "event": {
        "action": "down",
        "category": [
            "host"
        ],
        "code": "UPDOWN",
        "reason": "Line protocol on Interface GigabitEthernet1/0/13, changed state to down",
        "severity": 5,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2023-03-06T07:04:45.866000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "LINEPROTO"
            },
            "observer": {
                "interface": {
                    "name": "GigabitEthernet1/0/13"
                }
            }
        }
    },
    "host": {
        "name": "FE03.LOCAL"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    }
}
{
    "message": "STN01.LOCAL: Mar 6 2023 08:04:45.866 CET: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet1/0/13, changed state to up",
    "event": {
        "action": "up",
        "category": [
            "host"
        ],
        "code": "UPDOWN",
        "reason": "Line protocol on Interface GigabitEthernet1/0/13, changed state to up",
        "severity": 5,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2023-03-06T07:04:45.866000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "LINEPROTO"
            },
            "observer": {
                "interface": {
                    "name": "GigabitEthernet1/0/13"
                }
            }
        }
    },
    "host": {
        "name": "STN01.LOCAL"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    }
}
{
    "message": "FE05: Mar 6 2023 08:04:45.866: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/13, changed state to down",
    "event": {
        "action": "down",
        "category": [
            "host"
        ],
        "code": "UPDOWN",
        "reason": "Interface GigabitEthernet2/0/13, changed state to down",
        "severity": 3,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2023-03-06T08:04:45.866000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "LINK"
            },
            "observer": {
                "interface": {
                    "name": "GigabitEthernet2/0/13"
                }
            }
        }
    },
    "host": {
        "name": "FE05"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    }
}
{
    "message": "FE05: Mar 6 2023 08:04:45.866: %LINK-3-UPDOWN: Interface GigabitEthernet2/0/25, changed state to up",
    "event": {
        "action": "up",
        "category": [
            "host"
        ],
        "code": "UPDOWN",
        "reason": "Interface GigabitEthernet2/0/25, changed state to up",
        "severity": 3,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2023-03-06T08:04:45.866000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "LINK"
            },
            "observer": {
                "interface": {
                    "name": "GigabitEthernet2/0/25"
                }
            }
        }
    },
    "host": {
        "name": "FE05"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    }
}
{
    "message": "FE08: Jan 13 2023 10:16:05.33: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: jdoe] [Source: 1.2.3.4] [localport: 22] at 10:16:05 GMT Fri Jan 13 2023",
    "event": {
        "category": [
            "host"
        ],
        "code": "LOGIN_SUCCESS",
        "reason": "Login Success [user: jdoe] [Source: 1.2.3.4] [localport: 22] at 10:16:05 GMT Fri Jan 13 2023",
        "severity": 5,
        "type": [
            "access",
            "start"
        ]
    },
    "@timestamp": "2023-01-13T10:16:05.330000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "SEC_LOGIN"
            }
        }
    },
    "host": {
        "name": "FE08"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    },
    "related": {
        "ip": [
            "1.2.3.4"
        ],
        "user": [
            "jdoe"
        ]
    },
    "source": {
        "address": "1.2.3.4",
        "ip": "1.2.3.4",
        "port": 22
    },
    "user": {
        "name": "jdoe"
    }
}
{
    "message": "FE08: Jan 13 2023 10:16:05.33: %SYS-3-LOGGINGHOST_FAIL: Logging to host 3.2.4.5 port 514 failed",
    "event": {
        "category": [
            "host"
        ],
        "code": "LOGGINGHOST_FAIL",
        "reason": "Logging to host 3.2.4.5 port 514 failed",
        "severity": 3,
        "type": [
            "access",
            "end"
        ]
    },
    "@timestamp": "2023-01-13T10:16:05.330000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "SYS"
            }
        }
    },
    "destination": {
        "address": "3.2.4.5",
        "ip": "3.2.4.5",
        "port": 514
    },
    "host": {
        "name": "FE08"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    },
    "related": {
        "ip": [
            "3.2.4.5"
        ]
    }
}
{
    "message": "FE08: Jan 13 2023 10:16:05.33: %SYS-6-LOGOUT: User jdoe has exited tty session 2(1.2.3.4)",
    "event": {
        "category": [
            "host"
        ],
        "code": "LOGOUT",
        "reason": "User jdoe has exited tty session 2(1.2.3.4)",
        "severity": 6,
        "type": [
            "access",
            "end"
        ]
    },
    "@timestamp": "2023-01-13T10:16:05.330000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "SYS"
            },
            "observer": {
                "terminal": "2"
            }
        }
    },
    "host": {
        "name": "FE08"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    },
    "related": {
        "ip": [
            "1.2.3.4"
        ],
        "user": [
            "jdoe"
        ]
    },
    "source": {
        "address": "1.2.3.4",
        "ip": "1.2.3.4"
    },
    "user": {
        "name": "jdoe"
    }
}
{
    "message": "DN04.LOCAL: Feb 21 06:59:55.692: %SW_MATM-4-MACFLAP_NOTIF: Host 0011.2233.4455 in vlan 20 is flapping between port Gi1/0/9 and port Gi2/0/9",
    "event": {
        "category": [
            "host"
        ],
        "code": "MACFLAP_NOTIF",
        "reason": "Host 0011.2233.4455 in vlan 20 is flapping between port Gi1/0/9 and port Gi2/0/9",
        "severity": 4,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2024-02-21T06:59:55.692000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "SW_MATM"
            },
            "observer": {
                "interface": {
                    "ports": [
                        "Gi1/0/9",
                        "Gi2/0/9"
                    ]
                }
            }
        }
    },
    "host": {
        "name": "DN04.LOCAL"
    },
    "network": {
        "vlan": {
            "id": "20"
        }
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    },
    "source": {
        "mac": "00:11:22:33:44:55"
    }
}
{
    "message": "FE08: Jan 13 2023 10:16:05.33: %SYS-6-TTY_EXPIRE_TIMER: (exec timer expired, tty 2 (1.2.3.4)), user jdoe",
    "event": {
        "category": [
            "host"
        ],
        "code": "TTY_EXPIRE_TIMER",
        "reason": "(exec timer expired, tty 2 (1.2.3.4)), user jdoe",
        "severity": 6,
        "type": [
            "info"
        ]
    },
    "@timestamp": "2023-01-13T10:16:05.330000Z",
    "cisco": {
        "ios": {
            "event": {
                "facility": "SYS"
            },
            "observer": {
                "terminal": "2"
            }
        }
    },
    "host": {
        "name": "FE08"
    },
    "observer": {
        "product": "ios",
        "vendor": "Cisco"
    },
    "related": {
        "ip": [
            "1.2.3.4"
        ],
        "user": [
            "jdoe"
        ]
    },
    "source": {
        "address": "1.2.3.4",
        "ip": "1.2.3.4"
    },
    "user": {
        "name": "jdoe"
    }
}

Extracted Fields

The following table lists the fields that are extracted, normalized under the ECS format, analyzed and indexed by the parser. It should be noted that infered fields are not listed.

Name Type Description
@timestamp date Date/time when the event originated.
cisco.ios.event.facility keyword The facility of the event
cisco.ios.observer.interface.name keyword The name of the interface
cisco.ios.observer.interface.ports array The list of ports associated to the interface
cisco.ios.observer.terminal keyword The identifier of the terminal used for the action
destination.ip ip IP address of the destination.
destination.port long Port of the destination.
event.action keyword The action captured by the event.
event.category keyword Event category. The second categorization field in the hierarchy.
event.code keyword Identification code for this event.
event.reason keyword Reason why this event happened, according to the source
event.severity long Numeric severity of the event.
host.name keyword Name of the host.
network.vlan.id keyword VLAN ID as reported by the observer.
observer.product keyword The product name of the observer.
observer.vendor keyword Vendor name of the observer.
source.ip ip IP address of the source.
source.mac keyword MAC address of the source.
source.port long Port of the source.
user.name keyword Short name or login of the user.

Configure

Prerequisites

An internal log concentrator is required to collect and forward events to Sekoia.io.

Enable Syslog forwarding

Log on your Cisco appliance and follow this guide to enable syslog forwarding.

Create the intake

Go to the intake page and create a new intake from the format Cisco IOS.

Forward logs to Sekoia.io

Please consult the Syslog Forwarding documentation to forward these logs to Sekoia.io.

Further Readings