Cisco 350-701 - Implementing and Operating Cisco Security Core Technologies (SCOR 350-701)

DHCP option 82 is a feature that allows the network access device (NAD) to insert additional information into the DHCP request packet from the endpoint. This information can include the switch ID, port number, VLAN ID, and other attributes that can help Cisco ISE to identify and profile the endpoint. Cisco ISE can use DHCP option 82 to assign the endpoint to the appropriate identity group, policy, and authorization profile. DHCP option 82 is also useful to prevent rogue DHCP servers from assigning IP addresses to endpoints, as Cisco ISE can verify the legitimacy of the DHCP request based on the option 82 data. To use DHCP option 82, the NAD must be configured to enable this feature and send the option 82 data to Cisco ISE. Cisco ISE must also be configured to accept and parse the option 82 data from the NAD. For more details on how to configure DHCP option 82 on Cisco ISE and NAD, see the references below. References:

Configuring the DHCP Probe

Securing Your Network From DHCP Risks

Can we use ISE as DHCP/DNS server to prevent guest traffic using …

 DoS attacks are categorized as flood attacks or crash attacks. Flood attacks are the more common form of DoS attacks. They occur when the attacked system is overwhelmed by large amounts of traffic that the server is unable to handle. The system eventually stops. Some examples of flood attacks are ICMP flood, SYN flood, and UDP flood. Crash attacks are less frequent and they exploit flaws in the targeted system. The result is that the system crashes. Some examples of crash attacks are Ping of Death, Teardrop, and Land. References:

What is a denial-of-service (DoS) attack? | Cloudflare

What is a Denial of Service (DoS) attack? | Norton

What is a Denial of Service (DoS) Attack? | Cobalt

What is a denial of service attack (DoS) - Palo Alto Networks

To block all subdomains of domain.com, the administrator should configure the domain.com address in the block list. This is because Umbrella automatically applies a left side and right side wildcard to every domain in a block or allow destination list. Therefore, adding domain.com to a block list will result in requests to domain.com or its subdomains, such as www.domain.com, being blocked. Adding a wildcard character (*) is not supported and will not work. Adding the *.com address in the block list will block all domains that end with .com, which is not the desired outcome. References:

Understanding Destination lists supported entries and error messages

Wildcards and Destination Lists

 Cisco Identity Services Engine (ISE) and AnyConnect Posture module are the best solution to ensure that all endpoints are compliant before users are allowed access on the corporate network. ISE is a policy-based platform that provides secure network access, identity management, and endpoint compliance. AnyConnect Posture module is a component of the AnyConnect Secure Mobility Client that performs posture assessment and remediation on the endpoints. Together, they can enforce policies based on the endpoint’s compliance status, such as the presence and update of the corporate antivirus application and the Windows 10 build version. The administrator can configure posture requirements, profiles, and policies on ISE, and deploy them to the endpoints through AnyConnect. The endpoints will then report their posture status to ISE, which will grant or deny network access accordingly, or redirect them to a remediation portal if needed. References :

A destination list is a list of internet destinations: domains, URLs, and CIDRs. To control identity access to specific destinations, you can add destination lists to Umbrella and then select them when configuring your Web and DNS policies12. When you add or edit a destination list, the changes are applied immediately if the destination list is part of a policy3. This means that any identities that are associated with the policy will be affected by the changes in the destination list. You do not need to save the configuration or remove the destination list from the policy to apply the changes. However, you do need to have the appropriate user role to manage destination lists. The user role of Block Page Bypass or higher is needed to perform these changes4. References :=

Manage Destination Lists - Umbrella User Guide

Manage Destination Lists - Umbrella SIG User Guide

Add a Destination List - Umbrella User Guide

Add a DNS Destination List - Umbrella SIG User Guide

Cisco Umbrella and Cisco Duo Security are two solutions that help combat social engineering and phishing at the endpoint level. Cisco Umbrella is a cloud-based security platform that provides DNS-layer security, web filtering, and threat intelligence to protect users from malicious websites and domains. Cisco Duo Security is a multi-factor authentication (MFA) solution that verifies the identity of users and the health of their devices before granting access to applications. Both solutions help prevent attackers from compromising endpoints and stealing credentials or data through phishing or other social engineering techniques. References:

Cisco Umbrella

Cisco Duo Security

Implementing and Operating Cisco Security Core Technologies (SCOR) - Module 3: Cloud and Content Security

 A security application that notifies a controller within a software-defined network architecture about a specific security threat is using a northbound API. A northbound API is an interface that enables communication between the SDN controller and the applications or management systems that use the network services1. A security application can use a northbound API to send alerts, requests, or commands to the SDN controller, which can then take appropriate actions on the network devices or policies2. For example, a security application can use a northbound API to inform the SDN controller about a malicious traffic pattern, and the SDN controller can then block or redirect the traffic using a southbound API3.

 1: What is Software-Defined Networking (SDN)? | VMware Glossary 2: Intent-Based Networking’s Next Evolution: The DNA Center Platform - Cisco Blogs 3: Cisco SDN Security: Securing the Software Defined Network - Cisco

Microsegmentation is a network security technique that enables security architects to logically divide the data center or cloud environment into distinct security segments down to the individual workload level, and then define security controls and deliver services for each unique segment. Microsegmentation software with network virtualization technology is used to create zones in cloud deployments. These granular secure zones isolate workloads, securing them individually with custom, workload-specific policies. Microsegmentation uses a zero-trust model, which means that no traffic is allowed by default, and only explicitly authorized traffic is permitted based on the principle of least privilege. Microsegmentation helps to reduce the attack surface, prevent the lateral movement of threats, and strengthen regulatory compliance. The other options are incorrect because they do not describe microsegmentation accurately. Option B is incorrect because container orchestration platforms, such as Kubernetes, are used to automate the deployment, scaling, and management of containerized applications, but they do not provide microsegmentation by themselves. Option C is incorrect because private VLAN segmentation is a network security technique that isolates hosts within the same VLAN, but it does not provide granular security controls at the workload level. Option D is incorrect because host-based firewall rules are one of the components of microsegmentation, but they are not sufficient to implement microsegmentation without network virtualization and policy automation. References : What Is Microsegmentation? - Palo Alto Networks, What Is Micro-Segmentation? - Cisco, What is Micro-Segmentation? | VMware Glossary

The exhibit shows an access rule for URL filtering that has the following conditions:

The action is Block

The URL category is Botnets

The URL reputation is 3

The URL list is empty

This means that the rule will block any URL that matches the category and reputation criteria, regardless of the individual URL. According to the Cisco documentation1, the URL reputation is a score from 1 to 5 that indicates the risk level of a URL, where 1 is the most risky and 5 is the least risky. Therefore, a reputation score of 3 means a moderate risk level. The rule will not block URLs for botnets with reputation scores of 1, 2, 4, or 5, nor will it block any other URL category or list. The rule will also not allow any URL, as the action is Block, not Allow.

References := 1: Implementing and Operating Cisco Security Core Technologies (SCOR) v1.0, Module 4: Securing the Cloud, Lesson 4.3: Cloud Application Security, Topic 4.3.2: Cisco Umbrella, page 4-58.

To migrate a Cisco WSA virtual appliance from one physical host to another physical host by using VMware vMotion, both hosts must have access to the same defined network. This is because vMotion preserves the network identity and connections of the virtual machine, and requires that the source and destination hosts have compatible CPUs and shared storage1. The hosts do not need to run the same or different versions of Cisco AsyncOS, as long as they meet the minimum requirements for the virtual appliance2. The hosts do not need to use a different datastore than the virtual appliance, as vMotion can migrate virtual machines across datastores as well3. References: 1: VMware vMotion: Live Migration of Virtual Machines and Storage 2: Cisco Secure Web Appliance Virtual - Cisco 3: Migrating to Virtual SMA from Physical - Cisco Community

The crypto isakmp key command is used to configure a preshared key for ISAKMP authentication between two peers. The address 0.0.0.0 indicates that the key is valid for any peer address. Therefore, the same command must be entered on hostB with the same password in order to establish the tunnel with hostA. Changing the protocol to ikev2, using a different password, or changing the password to the default will not solve the problem, as they will create a mismatch in the authentication parameters. References:

Dynamic Multipoint VPN Configuration Guide, Cisco IOS Release 15M&T, section “Prerequisites for Dynamic Multipoint VPN (DMVPN)”

DMVPN - Concepts & Configuration, section “DMVPN - What is it?”

DMVPN Hub as the CA Server for the DMVPN Network Configuration Example, section “Prerequisites”

Explanation

Explanation

Security Intelligence Sources

…

Custom Block lists or feeds (or objects or groups)

Block specific IP addresses, URLs, or domain names using a manually-created list or feed (for IP addresses,

you can also use network objects or groups.)

For example, if you become aware of malicious sites or addresses that are not yet blocked by a feed, add these

sites to a custom Security Intelligence list and add this custom list to the Block list in the Security Intelligence

tab of your access control policy.