Rule Category

INDICATOR-SCAN -- Snort detected a system behavior that suggests the system has been affected by malware. That behavior is known as an Indicator of Compromise (IOC). The symptoms could be a wide range of behaviors, from a suspicious file name to an unusual use of a utility. Symptoms do not guarantee an infection; your network configuration may not be affected by malware, but showing indicators as a result of a normal function. This alert showed because Snort has detected a tool or script attempting to find objects on the network. This could be as simple as pinging a specific port that WordPress admins commonly use to see if a WordPress-targeted attack might succeed, or it could be as complex as attempting to create a map of the entire network, including ports, services, and devices. Snort scans the signature of this attempt to determine if it is different from the allowed network scanning tools (such as NMAP), and is therefore likely an attack.

Alert Message

INDICATOR-SCAN SSH brute force login attempt

Rule Explanation

freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demonstrated by an OpenSSH client with modified versions of ssh.c and sshconnect2.c. Impact: CVSS base score 9.3 CVSS impact score 10.0 CVSS exploitability score 8.6 confidentialityImpact COMPLETE integrityImpact COMPLETE availabilityImpact COMPLETE Details: Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Talos research team. This document was generated from data supplied by the national vulnerability database, a product of the national institute of standards and technology. For more information see [nvd].

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

Rule Vulnerability

CVE Additional Information

CVE-2012-6066
freeSSHd.exe in freeSSHd through 1.2.6 allows remote attackers to bypass authentication via a crafted session, as demonstrated by an OpenSSH client with modified versions of ssh.c and sshconnect2.c.
Details
SeverityHIGH Base Score9.3
Impact Score10.0 Exploit Score8.6
Confidentiality ImpactCOMPLETE Integrity ImpactCOMPLETE
Availability ImpactCOMPLETE Access Vector
AuthenticationNONE Ease of Access
CVE-2015-5600
The kbdint_next_device function in auth2-chall.c in sshd in OpenSSH through 6.9 does not properly restrict the processing of keyboard-interactive devices within a single connection, which makes it easier for remote attackers to conduct brute-force attacks or cause a denial of service (CPU consumption) via a long and duplicative list in the ssh -oKbdInteractiveDevices option, as demonstrated by a modified client that provides a different password for each pam element on this list.
Details
SeverityHIGH Base Score8.5
Impact Score7.8 Exploit Score10.0
Confidentiality ImpactPARTIAL Integrity ImpactNONE
Availability ImpactCOMPLETE Access Vector
AuthenticationNONE Ease of Access
CVE-2019-12700
A vulnerability in the configuration of the Pluggable Authentication Module (PAM) used in Cisco Firepower Threat Defense (FTD) Software, Cisco Firepower Management Center (FMC) Software, and Cisco FXOS Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper resource management in the context of user session management. An attacker could exploit this vulnerability by connecting to an affected system and performing many simultaneous successful Secure Shell (SSH) logins. A successful exploit could allow the attacker to exhaust system resources and cause the device to reload, resulting in a DoS condition. To exploit this vulnerability, the attacker needs valid user credentials on the system.
Details
SeverityMEDIUM Base Score6.8
Impact Score6.9 Exploit Score8.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactCOMPLETE Access VectorNETWORK
AuthenticationSINGLE Ease of AccessLOW
CVE-2019-15262
A vulnerability in the Secure Shell (SSH) session management for Cisco Wireless LAN Controller (WLC) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability exists because the SSH process is not properly deleted when an SSH connection to the device is disconnected. An attacker could exploit this vulnerability by repeatedly opening SSH connections to an affected device. A successful exploit could allow the attacker to exhaust system resources by initiating multiple SSH connections to the device that are not effectively terminated, which could result in a DoS condition.
Details
SeverityHIGH Base Score7.8
Impact Score6.9 Exploit Score10.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactCOMPLETE Access VectorNETWORK
AuthenticationNONE Ease of AccessLOW