Web Content Filter Monitoring

by Cody Dumont
August 14, 2014

Monitoring egress traffic is critical to preventing data loss, and the most common attack methods are client-side web attacks. The ability for LCE and PVS to monitor web traffic through logs and passive vulnerability detection can provide a much more in-depth view into web usage. Web attacks can be in the form of file download parsing; for example, a malformed PDF or JPEG could contain malware.

There are several vendor solutions with the ability to filter content based on several categories, and these systems should be configured to send log data to LCE and be passively monitored by PVS. The PVS scanners should be configured to send real-time syslog data to LCE. If the web filter appliance is not currently supported with normalized events by LCE, the organization should contact Tenable Customer Support and provide unnormalized log types. Once the LCE team creates the normalization rules, they will be uploaded to the LCE via scheduled updates.

This collection contains components that support indications of web content filtering alerts for the following vendor specific applications/appliances: Cisco, FortiGate, Palo Alto, SonicWALL, SecureSphere, McAfee, Sidewinder, MultiPot Veritas, Trend Micro, IIS, Blue Coat, F5, Squid, Suhosin, and WC3. Simply remove the components/indications that don't fit within your organization.

This collection of Web Content Filter components, used through SC CV combined with LCE, create a centralized solution for aggregation and viewing of web filter alert indications without the need to log into multiple devices to view data. Tenable’s Log Correlation Engine collects and aggregates data from multiple devices across the network infrastructure, with SC CV providing continuous real-time monitoring.

The dashboard and its components are available in the SecurityCenter Feed, an app store of dashboards, reports, and assets. The dashboard can be easily located in the SecurityCenter Feed by selecting category 'monitoring' and then selecting tags 'web', 'indicator', or 'monitoring'. The dashboard requirements are:

  • SecurityCenter 4.8.1
  • LCE 4.2.2

The components included in this collection are:

  • Web Content Filter Monitoring - URL Event Triggers - This component supports indications of URL event triggers for the following vendor-specific applications and appliances: Cisco, FortiGate, Palo Alto, SonicWALL, SecureSphere, McAfee, Sidewinder, MultiPot Veritas, Trend Micro, Suhosin, and WC3. Simply remove the indicators that don't fit within your organization. Triggered events from these devices are normalized by LCE and forwarded to SecurityCenter CV. These normalized event triggers are presented in an indicator type component with a purple color.
  • Web Content Filter Monitoring - Blue Coat Web Events - Blue Coat web filter events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized Blue Coat web content filter event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. Blue Coat logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - IIS Web Events - IIS web filter events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized IIS web content filter event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. IIS logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - Suhosin Events - Suhosin events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized Suhosin web content filter event. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. Suhosin logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - Web Request for File Type - This indicator component reports triggered events that include detection of file type extensions, such as audio files, executable files, images and others. These types of files could potentially contain malware or non-business related items, such as images and audio files.
  • Web Content Filter Monitoring - Apache Web Events - Apache web filter events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized Apache web content filter event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. Apache logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - HTTP GET and POST Errors - This component indicates on HTTP GET and POST triggered events. Triggered events are presented in an indicator type component with a purple color if any of the following GET/POST errors occur: Redirection, Server or Client.
  • Web Content Filter Monitoring - F5 Local Traffic Manager Proxied Connections - This component indicates specifically for F5 Local Traffic Manager proxy connection triggered events. Triggered events are presented in an indicator type component with a purple color if any of the following connection errors are present: LTM Client, LTM Server, or LTM Web.
  • Web Content Filter Monitoring - Blue Coat Admin Events - Blue Coat Admin events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component, displays each normalized Blue Coat Admin event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. Blue Coat Admin logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - Squid Web Error - Squid Web Error events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized Squid Web Error event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. Squid Web Error logs being actively forwarded to LCE are required for data to be present.
  • Web Content Filter Monitoring - W3C Web Server Events - This component is specific to W3C Web Server Error events. These events forwarded to Tenable’s LCE are processed and normalized. Event triggers are forwarded to SecurityCenter CV in the form of normalized events. This component displays each normalized W3C Web Server error event by type and time. Triggered events over the last 72 hours are presented in an indicator type component with a purple color. W3C Web Server error logs being actively forwarded to LCE are required for data to be present.