Cisco Blogs


Cisco Blog > Security

SHA512 Checksums for All Cisco Software

Cisco continues to strengthen the security in and around its products, solutions, and services. This week Cisco began providing a Secure Hash Algorithm (SHA) 512 bits (SHA512) checksum to validate downloaded images on www.cisco.com. Cisco already provided a Message Digest 5 (MD5) checksum as the secured hash of the software but the newer SHA512 hash value is now generated on all software images, creating a unique output that is more secure than the MD5 algorithm.

Read More »

Trust and Transparency

In our increasingly interconnected world, the Internet of Everything is making trust a critical element of how people use network-connected devices to work, play, live, and learn. The relentless rise in information security breaches underscores the deep need for enterprises to trust that their systems, data, business partners, customers, and citizens are safe.” – John N. Stewart, SVP and Chief Security and Trust Officer at Cisco

Trust and security is more important than ever before throughout the industry. Why aren’t customers explicitly demanding it be in all their IT systems? Why aren’t they demanding software developed with processes and technologies that drive security into all aspects of IT systems they buy? Why aren’t they demanding supply chain security and strong data protection? In short, why aren’t they demanding IT vendors produce more robust and secure solutions? Read More »

Tags: , , ,

New Email Security Release Adds Graymail Protection, Web Interaction Tracking, AMP Threat Grid, and More

Each day more than 100 billion corporate email messages are exchanged1. Who doesn’t need to do a little housekeeping and eliminate unwanted emails? But you need to think twice before you click on “unsubscribe.”

As you likely read in the 2015 Cisco Annual Security Report, attackers are using applications users inherently trust or view as benign, like web browser add-ons, to distribute malware. One of the latest phishing techniques is graymail – directing the “unsubscribe” link at the bottom of a seemingly innocuous marketing email to a malware infested website. Many of us click on these links without a second thought. But instead of ridding ourselves of unwanted emails, we’re actually opening ourselves up to an attack.

This is just one example of how attackers continue to innovate, and Cisco does as well. Our new AsyncOS release for Cisco Email Security Appliance (Cisco ESA) demonstrates how Cisco empowers you with a threat-centric approach to security and more comprehensive management control.

Read More »

Tags: , ,

Understanding Logjam and Future-Proofing Your Infrastructure

On May 19th, 2015 a team of researchers (Henninger et. al) published a paper with the title “Imperfect Forward Secrecy: How Diffie-Hellman Fails in Practice”.

The paper can be divided in two sections: 1) discrete logs on a 512-bit Diffie-Hellman (DH) group, and 2) a new attack against the Transport Layer Security (TLS) protocol. We’ll review both sections.
Read More »

Tags: , ,

Little Links, Big Headaches

This post was authored by Earl CarterJaeson Schultz.

Talos is always fascinated by the endless creativity of those who send spam. Miscreants who automate sending spam using botnets are of particular interest. Talos has been tracking a spam botnet that over the past several months that has been spamming weight loss products, male erectile dysfunction medication, and dating/casual sex websites.  These are all typical products one would expect to be purveyed through spam. What interests us about this spam are some of the ways the spam is constructed to try and evade detection (a.k.a. spam filters).

Beginning in March, Talos noted an absolute explosion in the usage of link shortening services in spam. After looking into the cause we found botnet ‘unknown2250’, as it is called by the Composite Block List (CBL), to be one of the primary parties responsible for this massive increase.

Click For Larger Image

Click For Larger Image

Read More »

Tags: , ,