---

Contents

1. About This Report
    1.1. Organisation
    1.2. Conventions
2. Security Audit
    2.1. Introduction
    2.2. Dictionary-based Password / Key
    2.3. Weak Passwords / Keys
    2.4. Directed Broadcasts
    2.5. Inbound TCP Connection Keep Alives
    2.6. HyperText Transport Protocol Service
    2.7. Simple Network Management Protocol
    2.8. ICMP Redirects
    2.9. Switch Port Trunking
    2.10. Switch Port Security
    2.11. Logging
    2.12. Proxy ARP
    2.13. Cisco Discovery Protocol
    2.14. BOOTP
    2.15. TCP and UDP Small Servers
    2.16. IP Unreachables
    2.17. Packet Assembler / Disassembler
    2.18. Maintenance Operations Protocol
    2.19. Conclusions
3. Device Configuration
    3.1. Introduction
    3.2. General
    3.3. Services
    3.4. Domain Name Settings
    3.5. Time Zone Settings
    3.6. User Accounts and Privilages
    3.7. Logging
    3.8. Simple Network Management Protocol
    3.9. Secure Shell
    3.10. Interfaces
    3.11. VTP Configuration
    3.12. Switchport Configuration
4. Appendix
    4.1. Abbreviations
    4.2. Common Ports
    4.3. Logging Severity Levels
    4.4. Time Zones
    4.5. Nipper Details

---

1. About This Report

1.1. Organisation

This Cisco Switch SBD1 report was produced by Nipper on Friday 24 March 2023. The report contains the following sections:
 

• a security audit report section that details any identified security-related issues. Each security issue includes a description of the issue, its impact, how easy it would be to exploit and a recommendation. The recommendations include, where appropriate, the command(s) to resolve the issue;
• a configuration report section that details the configuration settings;
• an abbreviations appendix section that expands any abbreviations used within the report;
• a common ports appendix section that details the TCP and UDP port numbers for the common services outlined within the report;
• an appendix section detailing the logging severity levels used by the logging facility;
• a time zones appendix section that details a number of the most commonly used time zones;
• an appendix section detailing the software used to produce this report.

1.2. Conventions

This report makes use of the text conventions outlined in Table 1.
 

Table 1: Report text conventions

Convention	Description
command	This text style represents the Cisco Switch command text that has to be entered literally.
string	This text style represents the Cisco Switch command text that the you have to enter.
[ ]	Used to enclose a Cisco Switch command option.
{ }	Used to enclose a Cisco Switch command requirement.
|	Divides command option or requirement choices.

 

---

2. Security Audit

2.1. Introduction

Nipper performed a security audit of the Cisco Switch SBD1 on Friday 24 March 2023. This section details the findings of the security audit together with the impact and recommendations.
 

2.2. Dictionary-based Password / Key

Observation: Attackers will often have dictionaries of words that contain names, places, default passwords and other common passwords. If a password or key is likely to be contained within an attacker's dictionary, they could gain access to the system.
 
The passwords and keys of the device SBD1 were tested against a small dictionary and one password / key was identified. The read-only Simple Network Management Protocol (SNMP) community string was public.
 
Impact: An attacker who was able to identify a password or key would be able to gain a level of access to the device, based on what service the password / key was used for.
 
Ease: Tools are available on the Internet that can perform dictionary-based password guessing against a number of network services.
 
Recommendation: Nipper strongly recommends that the password identified be immediately changed to something that is more difficult to guess. Nipper recommends that passwords be made up of at least eight characters in length and contain either uppercase or lowercase characters and numbers.
 

2.3. Weak Passwords / Keys

Observation: Strong passwords tend to contain a number of different types of character, such as uppercase and lowercase letters, numbers and punctuation characters. Weaker passwords tend not to contain a mixture of character types. Additionally, weaker passwords tend to be short in length.
 
Nipper identified two passwords / keys that did not meet the minimum password complexity requirements. These are listed in Table 2.
 

Table 2: Weak passwords / keys

Type	Service	Username	Password
Password	Enable	Level 15	contra_secreta.
Community	SNMP	read-only	public

 
Impact: If an attacker were able to gain a password or key, either through dictionary-based guessing techniques or by a brute-force method, the attacker could gain a level of access to SBD1.
 
Ease: A number of dictionary-based password guessing and password brute-force tools are available on the Internet.
 
Recommendation: Nipper strongly recommends that the weak passwords be immediately changed to ones that are stronger. Nipper recommends that passwords be made up of at least eight characters in length and contain either uppercase or lowercase characters and numbers.
 

2.4. Directed Broadcasts

Observation: Internet Control Message Protocol (ICMP) echo requests can be addressed to an entire network or subnet as well as to individual hosts. Disabling directed broadcasts on each individual network interface will help prevent network ping requests. Directed broadcasts are usually enabled by default on Cisco devices running Internet Operating System (IOS) version 11.3 and earlier.
 
Nipper determined that the device SBD1 had support for directed broadcasts enabled on the network interfaces listed in Table 3.
 

Table 3: Interfaces with directed broadcasts enabled

Interface	Description
FastEthernet0/1
FastEthernet0/5
Vlan10
Vlan30

 
Impact: A Denial of Service (DoS) attack exists that makes use of network echo requests, known as a smurf attack. An attacker would send an ICMP echo request with the victim hosts IP address spoofed as the source. The hosts on the network would then reply to the echo request, flooding the victim host.
 
Ease: Tools are available on the Internet that can perform the smurf attack outlined above.
 
Recommendation: Nipper recommends that directed broadcasts be disabled on all network interfaces. Directed broadcasts can be disabled on each individual network interface using the following command:
 

 

2.5. Inbound TCP Connection Keep Alives

Observation: Connections to a Cisco Switch device could become orphaned if a connection becomes disrupted. An attacker could attempt a DoS attack against a Cisco Switch by exhausting the number of possible connections. Transmission Control Protocol (TCP) keep alive messages can be configured to confirm that a remote connection is valid and then terminate any orphaned connections.
 
Nipper determined that TCP keep alive messages are not sent for connections from remote hosts.
 
Impact: An attacker could attempt a DoS by exhausting the number of possible connections.
 
Ease: Tools are available on the Internet that can open large numbers of TCP connections without correctly terminating them.
 
Recommendation: Nipper recommends that TCP keep alive messages be sent to detect and drop orphaned connections from remote systems. TCP keep alive messages can be enabled for connections from remote systems using the following command:
 

 

2.6. HyperText Transport Protocol Service

Observation: Recent Cisco IOS-based devices support web-based administration using the HTTP protocol. Cisco web-based administration facilities can sometimes be basic but they do provide a simple method of administering remote devices. However, HTTP is a clear-text protocol and is vulnerable to various packet-capture techniques.
 
Even though the HTTP service had not been configured, it can be enabled by default on some Cisco devices.
 
Impact: An attacker who was able to monitor network traffic could capture authentication credentials.
 
Ease: Network packet and password sniffing tools are widely available on the Internet. Once authentication credentials have been captured it is trivial to use the credentials to log in using the captured credentials.
 
Recommendation: Nipper recommends that, if not required, the HTTP service be disabled. If a remote method of access to the device is required, consider using HTTPS or Secure Shell (SSH). The encrypted HTTPS and SSH services may require a firmware or hardware upgrade. The HTTP service can be disabled with the following IOS command:
 
 
If it is not possible to upgrade the device to use the encrypted HTTPS or SSH services, additional security can be configured. An access list can be configured to restrict access to the device. An access list can be specified with the following command:
 

 
The authentication method can be changed using the following command (where the authentication method is either local, enable, tacacs or aaa):
 

 

2.7. Simple Network Management Protocol

Observation: SNMP is used to assist network administrators in monitoring and managing a wide variety of network devices. There are three main versions of SNMP in use. Versions 1 and 2 of SNMP are both secured with a community string and authenticate and transmit network packets without any form of encryption. SNMP version 3 provides several levels of authentication and encryption. The most basic level provides a similar protection to that of the earlier protocol versions. However, SNMP version 3 can be configured to provide encrypted authentication (auth) and secured further with support for encrypted data communications (priv).
 
Nipper determined that SNMP protocol version 1 was configured on SBD1.
 
Impact: Due to the unencrypted nature of SNMP protocol versions 1 and 2c, an attacker who was able to monitor network traffic could capture device configuration settings, including authentication details.
 
Ease: Network packet monitoring and capture tools are widely available on the Internet and SNMP tools are included as standard with some operating systems.
 
Recommendation: Nipper recommends that, if possible, SNMP version 1 be disabled. Furthermore, Nipper recommends that, if SNMP is required, protocol version 3 be configured with Auth and Priv authentication. SNMP protocol version 1 can be disabled with the following command for each community string:
 
 
SNMP version 3 Auth and Priv access can be configured with the following commands:
 
 

 

2.8. ICMP Redirects

Observation: ICMP redirect messages allow systems to change the route that network traffic takes. On networks with functional network routing, disabling ICMP redirects will have little to no effect. ICMP redirects are usually enabled by default on Cisco devices.
 
Nipper determined that the device SBD1 had support for ICMP redirects enabled on the network interfaces listed in Table 4.
 

Table 4: Interfaces with ICMP redirects enabled

Interface	Description
Vlan10
Vlan30

 
Impact: An attacker could use ICMP redirect messages to route network traffic through their own router, possibly allowing them to monitor network traffic.
 
Ease: Tools are widely available that can send ICMP redirect messages.
 
Recommendation: Nipper recommends that, if not required, ICMP redirects be disabled on all network interfaces. ICMP redirects can be disabled on each individual network interface using the following command:
 

 

2.9. Switch Port Trunking

Observation: Cisco Switch devices are able to transfer Virtual Local Area Network (VLAN) packets to different network devices, extending a VLAN across different physical devices. In order to extend a VLAN to a different physical device, a trunk has to be created between the devices. Cisco Switch devices default to allowing a trunk to be negotiated on a particular switch port if the connected device will also allow the trunk and supports a common trunking protocol.
 
Nipper determined that one switch port allowed a trunk to be negotiated. The switch port FastEthernet0/1 allowed trunking.
 
Impact: An attacker who was able to create a trunk would gain direct access to all the VLANs extended over the trunk. This would allow an attacker to bypass any network filtering between the VLANs.
 
Ease: The attacker would require knowledge of network trunking. However, tools are available on the Internet that can exploit trunking vulnerabilities.
 
Recommendation: Nipper recommends that, where possible, all switch ports be configured to provide no trunking. If trunking is required on a specific switch port, Nipper recommends that the switch port be configured to trunk only the required VLANs. Switch ports can be configured to provide no trunking on each interface with the following commands:
 
 

 

2.10. Switch Port Security

Observation: Switch port security enables a Cisco Switch to help prevent unauthorised access to the network by limiting the Media Access Control (MAC) addresses allowed on specific ports. MAC addresses can either be specified for a particular switch port or can be learned by the Cisco Switch. When port security is configured a variety of actions can be taken when a violation occurs, such as automatically disabling the port.
 
Nipper identified two switch ports that had no port security configured, these are listed in Table 5.
 

Table 5: Switch ports with no port security

Interface	Description
FastEthernet0/1
FastEthernet0/5

 
Impact: A switch port with no configured port security could allow an attacker to attach an unauthorised device and scan other network attached devices. Depending on the security of the network attached devices, this issue could allow an attacker to perform information gathering, or potentially, gain access to vulnerable devices.
 
Ease: An attacker would have to gain access to a switch port with no security configured. If the switch port is not directly patched to a wall socket, the attacker would have to gain physical access to the Cisco Switch.
 
Recommendation: Nipper recommends that, where possible, port security be enabled on all switch ports. Furthermore, Nipper recommends that all switch ports that are not used be shutdown. Switch port security with MAC address learning and port shutdown on a violation can be configured on each interface with the following commands:
 
 
 
 
Unused interfaces can be disabled with the following interface command:
 

 

2.11. Logging

Observation: Logging is an essential component of a secure network configuration. Logging not only assists network administrators to identify issues when troubleshooting, but enables network administrators to react to intrusion attempts or Denial-of-Service attacks. It is therefore critical that logs be monitored, allowing administrators to take immediate action when an attack has been identified. Furthermore, system logs are a key component of a forensic investigation into past intrusions or service disruptions.
 
Nipper determined that, although logging was enabled on SBD1, Syslog logging was not configured.
 
Impact: An attacker could attempt to map and bypass any configured Access Control List (ACL) or to gain access to the Cisco Switch without network administrators being alerted to the attempts. Furthermore, after an unauthorised intrusion into the network had been detected, it would be more difficult for an investigation to identify the source of the attack or the entry point without access to logs.
 
Ease: N/A
 
Recommendation: Nipper recommends that Syslog and Buffered logging be configured on SBD1. Logging can be enabled with the following command:
 

 
To configure Syslog logging, four things need to be set; a source interface for the Syslog messages to be sent from, one or more Syslog hosts to send messages to, the Syslog logging message severity level and the Syslog facility. The following commands can be used to configure Syslog logging:
 
 
 
 

 
It is worth noting that older IOS versions do not exclude the host parameter when specifying a host to send Syslog messages to. For older IOS versions you would use the following command:
 

 

2.12. Proxy ARP

Observation: Address Resolution Protocol (ARP) is a protocol that network hosts use to translate network addresses into media addresses. Under normal circumstances, ARP packets are confined to the sender's network segment. However, a Cisco router with Proxy ARP enabled on network interfaces can act as a proxy for ARP, responding to queries and acting as an intermediary.
 
Nipper identified two interfaces that had Proxy ARP enabled. These are listed in Table 6.
 

Table 6: Interfaces with Proxy ARP enabled

Interface	Description
Vlan10
Vlan30

 
Impact: A router that acts as a proxy for ARP requests will extend layer two access across multiple network segments, breaking perimeter security.
 
Ease: A Cisco device with Proxy ARP enabled will proxy ARP requests for all hosts on those interfaces.
 
Recommendation: Nipper recommends that, if not required, Proxy ARP be disabled on all interfaces. Proxy ARP can be disabled on each interface with the following Cisco IOS command:
 

 

2.13. Cisco Discovery Protocol

Observation: Cisco Discovery Protocol (CDP) is a proprietary protocol that is primarily used by Cisco, but has been used by others. CDP allows some network management applications and CDP aware devices to identify each other on a Local Area Network (LAN) segment. Cisco devices, including switches, bridges and routers are configured to broadcast CDP packets by default. The devices can be configured to disable the CDP service or disable CDP on individual network interfaces.
 
Nipper determined that the CDP service had not been disabled, and additionally, had not been disabled on all the active network interfaces.
 
Impact: CDP packets contain information about the sender, such as hardware model information, operating system version and IP address details. This information would allow an attacker to gain information about the configuration of the network infrastructure.
 
Ease: CDP packets are broadcast to an entire network segment. An attacker could use one of the many publicly available tools to capture network traffic and view the leaked information.
 
Recommendation: Nipper recommends that, if not required, the CDP service be disabled on the Cisco device SBD1. If CDP is required, Nipper recommends that CDP be disabled on all interfaces except those that are explicitly required.
 
The CDP service can be disabled by issuing the following Cisco IOS command:
 
 
CDP can be disabled on individual interfaces using the following command:
 
 
In some configurations with IP phones, deployed using either Auto Discovery or Dynamic Host Configuration Protocol (DHCP), the CDP service may need to be enabled. In this situation CDP should be disabled on all network interfaces for which it is not required.
 

2.14. BOOTP

Observation: BOOTstrap Protocol (BOOTP) is a datagram protocol that allows compatible hosts to load their operating system over the network from a BOOTP server. Cisco routers are capable of acting as BOOTP servers for other Cisco devices and the service is enabled by default. However, BOOTP is rarely used and may represent a security risk.
 
Nipper determined that BOOTP was not disabled. However, it is worth noting that not all Cisco devices support BOOTP.
 
Impact: An attacker could use the BOOTP service to download a copy of the router's IOS software.
 
Ease: Tools are available on the Internet to access BOOTP servers.
 
Recommendation: Nipper recommends that, if not required, the BOOTP service be disabled. The following command can be used to disable BOOTP:
 

 

2.15. TCP and UDP Small Servers

Observation: Cisco devices provide a set of simple servers which are collectively known as TCP small servers and User Datagram Protocol (UDP) small servers. The services provide little functionality and include chargen, echo and daytime. Cisco IOS version 11.2 and older enable these services by default; newer IOS versions explicitly require them to be started.
 
Nipper determined that the version of IOS, on the Cisco device SBD1, enables these servers by default and they have not been explicitly disabled.
 
Impact: Each running service increases the chances of an attacker being able to identify the device and successfully compromise it. It is good security practice to disable all unused services.
 
Ease: Tools are widely available to query these services and some operating systems install these tools by default.
 
Recommendation: Nipper recommends that, if not required, TCP and UDP small servers be explicitly disabled. TCP and UDP small services are rarely used and are disabled by default in newer versions of Cisco IOS.
 
TCP small servers can be disabled with the following IOS command:
 

 
UDP small servers can be disabled with the following IOS command:
 

 

2.16. IP Unreachables

Observation: ICMP IP unreachable messages can be generated by a Cisco device when a host attempts to connect to a non-existent host, network, or use an unsupported protocol. ICMP IP unreachable messages will let the connecting host know that the host, network or protocol is not supported or cannot be contacted. Therefore, the host does not have to wait for a connection time-out. ICMP IP unreachable messages are normally enabled by default on Cisco devices and must be explicitly disabled.
 
Nipper determined that the Cisco device SBD1 had ICMP IP unreachable messages enabled on the interfaces listed in Table 7.
 

Table 7: Interfaces with IP unreachables enabled

Interface	Description
Vlan10
Vlan30

 
Impact: An attacker who was performing network scans to determine what services were available would be able to scan a device more quickly.
 
Ease: Tools are available on the Internet that can perform a wide variety of scan types.
 
Recommendation: Nipper recommends that, if not required, IP unreachables be disabled on all network interfaces. However, whilst disabling IP unreachables will not stop scans, it does make it more difficult for an attacker. The IP unreachables option is disabled or enabled individually for each network interface. It can be disabled with the following command:
 

 

2.17. Packet Assembler / Disassembler

Observation: The Packet Assembler / Disassembler (PAD) service enables X.25 connections between network systems. The PAD service is enabled by default on most Cisco IOS devices but it is only required if support for X.25 links is necessary.
 
Nipper determined that the PAD service had not been disabled.
 
Impact: Running unused services increases the chances of an attacker finding a security hole or fingerprinting a device.
 
Ease: N/A
 
Recommendation: Nipper recommends that, if not required, the PAD service be disabled. Use the following command to disable the PAD service:
 

 

2.18. Maintenance Operations Protocol

Observation: Maintenance Operations Protocol (MOP) is used with the DECnet protocol suite. MOP is enabled by default on ethernet interfaces in some versions of IOS.
 
Nipper determined that MOP had not been disabled on all ethernet interfaces.
 
Impact: Running unused services increases the chances of an attacker finding a security hole or fingerprinting a device.
 
Ease: N/A
 
Recommendation: Nipper recommends that, if not required, MOP be disabled on all ethernet interfaces. MOP can be disabled on each interface with the following command:
 

 

2.19. Conclusions

Nipper performed a security audit of the Cisco Switch device SBD1 on Friday 24 March 2023 and identified 17 security-related issues. Nipper determined that:
 

• dictionary-based passwords / keys were in use;
• weak passwords / keys were identified;
• directed broadcasts were enabled;
• TCP keep alive messages are not configured for inbound connections;
• clear-text remote web-based administration was enabled using HTTP;
• clear-text remote administration was enabled using SNMP;
• ICMP redirects were not disabled for all network interfaces;
• trunk negotiation was not disabled on all switch ports;
• port security was not enabled on all switch ports;
• insufficient logging was configured;
• ARP request proxying was not disabled on all network interfaces;
• CDP was not disabled;
• BootP was enabled;
• all small servers have not been disabled;
• IP unreachables have not been disabled on all interfaces;
• the PAD service was enabled;
• MOP had not been disabled on all interfaces.

---

3. Device Configuration

3.1. Introduction

This section details the configuration settings of the Cisco Switch device SBD1.
 

3.2. General

Table 8: General device settings

Description	Setting
Hostname	SBD1
Service Password Encryption	Enabled
BOOTP	Enabled
Service Config	Disabled
TCP Keep Alives (In)	Disabled
TCP Keep Alives (Out)	Disabled

 

3.3. Services

Table 9: Device services

Service	Status
Telnet	Disabled
HTTP	Unconfigured
Finger	Disabled
TCP Small Services	Enabled
UDP Small Services	Enabled
SNMP	Enabled
CDP	Enabled
PAD	Enabled

 

3.4. Domain Name Settings

Table 10: Domain name settings

Description	Setting
Domain Name	islacinco.com
Domain Lookup	Disabled
DNS Server 1	5.5.5.5

 

3.5. Time Zone Settings

Table 11: Time zone settings

Description	Setting
Time Zone	UTC
UTC Offset	None
Summer Time Zone	Disabled
Authorative Time Source	No

 

3.6. User Accounts and Privilages

Table 12: Enable Passwords

Level	Password	Encryption
15	contra_secreta.	None

 

Table 13: User Accounts

Username	Privilage	Password	Encryption
leidi	15	<unknown>	Unknown
wilberth	15	<unknown>	Unknown
bianca	15	<unknown>	Unknown
jared	15	<unknown>	Unknown

 
Login banners should provide a warning against unauthorised access to the device. The configured banner on SBD1 was:
 
Acceso no autorizado prohibido. Solo personal autorizado."
line con 0
exec-timeout 5 0
password linea_de_consola.
login
line vty 0 4
password linea_vty.
login local
transport input ssh
line vty 5 15
password linea_vty.
login local
transport input ssh
exit
service timetamps log datetime msec
loggin facility syslog
loggin trap debug
logging host 10.5.20.20

 

3.7. Logging

Table 14: Logging configuration

Description	Setting
Logging	Enabled
Log Configuration Changes	Disabled
Console Logging	System Default
Console Logging Severity Level	Default
Syslog Logging	Disabled
Buffer Logging	System Default
Buffer Size	Default
Buffer Logging Severity Level	Debugging (7)
Terminal Line Logging	Enabled
Terminal Line Logging Severity Level	Debugging (7)

 

3.8. Simple Network Management Protocol

SNMP is used to assist network administrators in monitoring and managing a wide variety of network devices. There are three main versions of SNMP in use. Versions 1 and 2 of SNMP are both secured with a community string and authenticate and transmit network packets without any form of encryption. SNMP version 3 provides several levels of authentication and encryption. The most basic level provides a similar protection to that of the earlier protocol versions. However, SNMP version 3 can be configured to provide encrypted authentication (auth) and secured further with support for encrypted data communications (priv).
 

Table 15: General SNMP service configuration

Description	Setting
Service enabled	Yes
Trap Timeout	30 seconds
TFTP Server List	Disabled

 

Table 16: SNMP community strings

Community	Access	View	Access-List	Enabled
public	Read-Only			Yes

 

Table 17: SNMP traps

SNMP Trap

 

3.9. Secure Shell

Table 18: SSH configuration

Description	Setting
SSH	Disabled
Protocol version	2
Login time-out	Default
Login retries	Default

 

3.10. Interfaces

Table 19: Interfaces

Interface	Active	IP Address	Proxy ARP	IP Unreachable	IP Redirect	IP Mask Reply	IP Direct Broadcast	NTP	CDP	MOP
FastEthernet0/1	Yes	None	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
FastEthernet0/5	Yes	None	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
Vlan10	Yes	10.5.10.252 255.255.255.0	On	On	On	Off	On	On	N/A	On
Vlan30	Yes	10.5.30.252 255.255.255.0	On	On	On	Off	On	On	N/A	On

 

3.11. VTP Configuration

Table 20: VTP configuration

Description	Setting
VTP Mode	Server

 

3.12. Switchport Configuration

Table 21: Switchport configuration

Interface	Active	Description	VLAN	Mode	Port Security	Security Violation
FastEthernet0/1	Yes		1	Trunk	Off	Shutdown
FastEthernet0/5	Yes		10	Access	Off	Shutdown

 

---

4. Appendix

4.1. Abbreviations

ACL	Access Control List
ARP	Address Resolution Protocol
BOOTP	BOOTstrap Protocol
CDP	Cisco Discovery Protocol
DHCP	Dynamic Host Configuration Protocol
DoS	Denial of Service
HTTP	HyperText Transfer Protocol
HTTPS	HyperText Transfer Protocol over SSL
ICMP	Internet Control Message Protocol
IOS	Internet Operating System
IP	Internet Protocol
LAN	Local Area Network
MAC	Media Access Control
MOP	Maintenance Operations Protocol
NTP	Network Time Protocol
PAD	Packet Assembler / Disassembler
SNMP	Simple Network Management Protocol
SSH	Secure Shell
SSL	Secure Sockets Layer
TCP	Transmission Control Protocol
TFTP	Trivial File Transfer Protocol
UDP	User Datagram Protocol
UTC	Coordinated Universal Time
VLAN	Virtual Local Area Network
VTP	VLAN Trunking Protocol

 

4.2. Common Ports

Table 22: Common ports

Service	Port
SSH	22
DHCP	67
TFTP	69
HTTP	80
NTP	123
SNMP	161
HTTPS	443

 

4.3. Logging Severity Levels

Table 23: Logging message severity levels

Level	Level Name	Description
0	Emergencies	System is unstable
1	Alerts	Immediate action is required
2	Critical	Critical conditions
3	Errors	Error conditions
4	Warnings	Warning conditions
5	Notifications	Significant conditions
6	Informational	Informational messages
7	Debugging	Debugging messages

 

4.4. Time Zones

Table 24: Common time zone acronyms

Region	Acronym	Time Zone	UTC Offset
Australia	CST	Central Standard Time	+9.5 hours
Australia	EST	Eastern Standard/Summer Time	+10 hours
Australia	WST	Western Standard Time	+8 hours
Europe	BST	British Summer Time	+1 hour
Europe	CEST	Central Europe Summer Time	+2 hours
Europe	CET	Central Europe Time	+1 hour
Europe	EEST	Eastern Europe Summer Time	+3 hours
Europe	EST	Eastern Europe Time	+2 hours
Europe	GMT	Greenwich Mean Time
Europe	IST	Irish Summer Time	+1 hour
Europe	MSK	Moscow Time	+3 hours
Europe	WEST	Western Europe Summer Time	+1 hour
Europe	WET	Western Europe Time	+1 hour
USA and Canada	ADT	Atlantic Daylight Time	-3 hours
USA and Canada	AKDT	Alaska Standard Daylight Saving Time	-8 hours
USA and Canada	AKST	Alaska Standard Time	-9 hours
USA and Canada	AST	Atlantic Standard Time	-4 hours
USA and Canada	CDT	Central Daylight Saving Time	-5 hours
USA and Canada	CST	Central Standard Time	-6 hours
USA and Canada	EDT	Eastern Daylight Time	-4 hours
USA and Canada	EST	Eastern Standard Time	-5 hours
USA and Canada	HST	Hawaiian Standard Time	-10 hours
USA and Canada	MDT	Mountain Daylight Time	-6 hours
USA and Canada	MST	Mountain Standard Time	-7 hours
USA and Canada	PDT	Pacific Daylight Time	-7 hours
USA and Canada	PST	Pacific Standard Time	-3 hours

 

4.5. Nipper Details

This report was generated using Nipper version 0.11.7. Nipper is an Open Source tool designed to assist security professionals and network system administrators securely configure network infrastructure devices. The latest version of Nipper can be found at the following URL:
 
http://nipper.sourceforge.net.