Vce 350-701 Questions Latest

 IOS zone-based firewalls (ZBFW) are a feature that provides stateful firewall policies between groups of interfaces known as zones. A zone is a logical grouping of one or more interfaces that have similar security requirements. A zone can be applied to physical interfaces, subinterfaces, port channels, VLAN interfaces, or tunnel interfaces. However, an interface can be assigned only to one zone, and it cannot be shared between zones. This is because the ZBFW policy is applied between zones, not interfaces, and it controls the bidirectional traffic flow between them. Therefore, an interface can belong to only one zone at a time, and it must be removed from one zone before it can be added to another zone. This ensures that the firewall policy is consistent and unambiguous for each interface.

References :=

• Security Configuration Guide: Zone-Based Policy Firewall, Cisco IOS XE Gibraltar 16.12.x, Configuring Zones
• Understand the Zone-Based Policy Firewall Design, Zone-Based Policy Overview
• IOS Zone Based Firewall Step-by-Step Basic Configuration, Zone Based Firewall Vs CBAC

Cisco ASA NetFlow v9 Secure Event Logging (NSEL) is a security logging mechanism that is built on NetFlow Version 9 technology and provides stateful, IP flow tracking for significant events in a flow. NSEL requires a collector to receive and process the exported data records. To configure NSEL, you need to define a flow-export event type under a policy using the Modular Policy Framework (MPF). The event type specifies which events to export, such as flow-create, flow-denied, flow-teardown, flow-update, or all. You also need to configure the NSEL collectors, the template timeout intervals, and the flow-update interval. Optionally, you can disable the redundant syslog messages and reset the runtime counters.

The other statements are false because:

• To view bandwidth usage for NetFlow records, the QoS feature is not required. You can use a NetFlow collector or analyzer to view the bandwidth usage and other statistics from the exported data records.
• A sysopt command cannot be used to enable NSEL on a specific interface. NSEL is enabled globally on all interfaces by default when you configure a flow-export event type under a policy.
• NSEL cannot be used without a collector configured. NSEL exports data records to the configured collectors using NetFlow over UDP. If no collector is configured, the data records are discarded.

References:

• NetFlow Secure Event Logging (NSEL) - Cisco, Topic: Configuring NSEL, page 48-5
• Cisco Secure Firewall ASA NetFlow Implementation Guide, Topic: Configure NSEL Collectors (CLI), Configure Flow-Export Actions Through Modular Policy Framework, Configure Template Timeout Intervals, Change the Time Interval for Sending Flow-Update Events to a Collector, Disable and Reenable NetFlow-related Syslog Messages, Reset Runtime Counters
• Configuring NetFlow on ASA with ASDM - Cisco Community, Topic: Enable NetFlow (ASDM)

Cross-site scripting (XSS) is a web security vulnerability that allows an attacker to inject malicious code into a web page that is viewed by other users. XSS can compromise the user’s interaction with the web application, steal sensitive data, perform unauthorized actions, and more. To prevent XSS, web developers need to apply various defensive techniques to ensure that user-supplied data is not interpreted as code by the browser. Two of these techniques are:

• Incorporate contextual output encoding/escaping: This means that any user-supplied data that is displayed on the web page should be properly encoded or escaped according to the context where it appears. For example, if the data is inserted into an HTML attribute, it should be HTML attribute encoded; if the data is inserted into a JavaScript string, it should be JavaScript string encoded; and so on. This prevents the data from breaking out of its intended context and being executed as code by the browser. Output encoding should be done by using a reliable library or framework that supports different contexts and encodings.
• Run untrusted HTML input through an HTML sanitization engine: This means that any user-supplied data that is intended to contain HTML markup should be filtered and validated by a sanitization engine that removes or escapes any potentially dangerous elements, attributes, or scripts. This prevents the attacker from injecting malicious HTML code that can execute scripts, load external resources, redirect the user, or perform other malicious actions. HTML sanitization should be done by using a well-tested and maintained library or framework that follows the best practices and standards for HTML filtering.

References :=

• [Implementing and Operating Cisco Security Core Technologies (SCOR) v1.0], Module 5: Securing the Cloud, Lesson 5.2: Web Application Security, Topic 5.2.2: Cross-Site Scripting (XSS)
• Cross Site Scripting Prevention Cheat Sheet - OWASP
• What is cross-site scripting (XSS) and how to prevent it? - Web Security Academy

 The Decrypt for Application Detection feature within the WSA Decryption options enhances the ability of AsyncOS to detect HTTPS applications. The HTTPS Proxy can decrypt HTTPS connections to web applications. This allows the Application Visibility and Control (AVC) engine to more accurately detect and block web applications that use HTTPS. This feature can help improve the security and performance of the network by identifying and controlling the usage of web applications that may consume bandwidth, pose security risks, or violate compliance policies.

References:

• WSA decryption options - Cisco Community, Topic: Decrypt for Application Detection
• User Guide for AsyncOS 11.7 for Cisco Web Security Appliances - GD (General Deployment) - Create Decryption Policies to Control HTTPS Traffic, Topic: Overview of Create Decryption Policies to Control HTTPS Traffic, Decryption for Application Detection