incident response

October 2, 2013

SECURITY

Using DNS RPZ to Block Malicious DNS Requests

3 min read

After delivering several presentations at Cisco Live and Cisco Connect this year, I received a few questions regarding DNS Response Policy Zones (RPZ) and how can they be used to block DNS resolution to known malicious hosts and sites. I decided to write this short post to explain what it is and provide several pointers. […]

July 9, 2013

SECURITY

TMA? Get Some Relief from Acronym Overload

10 min read

I see and hear a variety of acronyms being used on a daily basis. I recently heard one tossed around with good humor that makes a point: TMA or Too Many Acronyms. Every once in a while, when I think I’ve embedded the definition and use of an acronym into my long-term memory (anything beyond […]

May 1, 2013

SECURITY

Coordinated Attacks Against the U.S. Government and Banking Infrastructure

8 min read

Prologue On April 10, 2013, a collective of politically motivated hacktivists announced a round of planned attacks called #OPUSA. These attacks, slated to begin May 7, 2013, are to be launched against U.S.-based targets. #OPUSA is a follow-up to #OPISRAEL, which were a series of attacks carried out on April 7 against Israeli-based targets. Our goal here is to […]

April 2, 2013

SECURITY

I Can’t Keep Up with All These Cisco Security Advisories: Do I Have to Upgrade?

11 min read

"A security advisory was just published! Should I hurry and upgrade all my Cisco devices now?" This is a question that I am being asked by customers on a regular basis. In fact, I am also asked why there are so many security vulnerability advisories. To start with the second question: Cisco is committed to protecting customers by sharing critical security-related information in a very transparent way. Even if security vulnerabilities are found internally, the Cisco Product Security Incident Response Team (PSIRT) – which is my team – investigates, drives to resolution, and discloses such vulnerabilities. To quickly answer the first question, don't panic, as you may not have to immediately upgrade your device. However, in this article I will discuss some of the guidelines and best practices for responding to Cisco security vulnerability reports.