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Cisco IPS Signature Coverage for OpenSSL Heartbleed Issue

The Cisco IPS Signature Development team has released 4 signature updates in the past week. Each of the updates contains either modifications to existing signatures or additional signatures for detection of attacks related to the OpenSSL Heartbleed issue. I’m going to take a moment to summarize the signature coverage.

To best utilize your Cisco IPS to protect against the OpenSSL Heartbleed issue:

  • Update your sensors to signature update pack S788.
  • Enable and activate sub-signatures /3 and /4 for signature 4187, leaving /0, /1, and /2 disabled and retired (by default, signature 4187 is disabled and retired across all sub-signatures).
  • Sub-signatures /3 and /4 are set at a severity of Informational and Low, respectively, and will not drop traffic by default. If after monitoring the sensor alerts, you are comfortable dropping traffic inline based on those alerts, you will need to add an action of “deny-packet” to each signature.

Further detail regarding the released signatures:
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The Internet of Everything, Including Malware

December 4, 2013 at 1:09 pm PST

We are witnessing the growth of the Internet of Everything (IoE), the network of embedded physical objects accessed through the Internet, and it’s connecting new devices to the Internet which may not traditionally have been there before. Unfortunately, some of these devices may be deployed with a security posture that may need improvement.

Naturally when we saw a few posts about multi-architecture malware focused on the “Internet of Things”, we decided to take a look. The issue being exploited in those posts is CVE-2012-1823, which has both an existing Cisco IPS signature as well as some for Snort. It turns out this vulnerability is actually quite heavily exploited by many different worms, and it took quite a bit of effort to exclude all of the alerts generated by other pieces of malware in Cisco IPS network participation. Due to the vulnerability-specific nature of the Cisco IPS signature, the same signature covers this issue as well as any others that use this technique; just one signature provides protection against all attempts to exploit this vulnerability.  As you can see in the graph below this is a heavily exploited vulnerability. Note that these events are any attack attempting to exploit this issue, not necessarily just the Zollard worm.

The graph below is derived from both Cisco IPS and Sourcefire IPS customers. The Cisco data is from customers who have ‘opted-in’ to network participation. This service is not on by default. The Sourcefire data below is derived from their SPARK network of test sensors. This graph is showing the percent increase of alert volume from the normal for each dataset at the specified time.

zollard_cisco_sf

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

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 summarize and inform readers of resources, recommendations, network mitigations, and best practices that are available to prevent, mitigate, respond to, or dilute the effectiveness of these attacks. This blog was a collaborative effort between myself, Kevin TimmJoseph KarpenkoPanos Kampanakis, and the Cisco TRAC team.

Analysis

If the attackers follow the same patterns as previously witnessed during the #OPISRAEL attacks, then targets can expect a mixture of attacks. Major components of previous attacks consisted of denial of service attacks and web application exploits, ranging from advanced ad-hoc attempts to simple website defacements. In the past, attackers used such tools as LOICHOIC, and Slowloris.

Publicly announced attacks of this nature can have highly volatile credibility. In some cases, the announcements exist only for the purpose of gaining notoriety. In other cases, they are enhanced by increased publicity. Given the lack of specific details about participation or capabilities, the exact severity of the attack can’t be known until it (possibly) happens. Read More »

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Why the Cisco SIO Portal Doesn’t Give Out Candy

“Change is inevitable—except from a vending machine.”

In the spirit of Robert C. Gallagher’s famous quote—and in our quest to never be a vending machine—we’ve rolled out several updates to Cisco’s Security Intelligence Operations (SIO) Portal which I trust you will find useful. Thanks to your feedback, we continue to evolve the Portal to ensure that relevant security content is where you need it, when you need it. Providing timely information to our customers requires not only a global team of Cisco security experts to pipeline the latest information, but a complementary team who ensures that the most significant issues are also the most visible. In fact, that’s the most exciting change we made: a new ‘Security Highlights’ tab which allows a cross-functional group, led by our content managers, to call out the most important issues to our customers. That way, instead of looking at IntelliShield alerts, Cisco Security Notices, or Event Responses individually when time is scarce, this new tab gives you an at-a-glance view of Cisco security content our experts feel is most pressing given all of the events into which we have a view.

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Who Keeps Your IPS Up To Date?

The realm of Network security encompasses many perspectives and interests as is evident from the wealth of articles prevalent across the media and availability of various proactive protection measures. One particular technology recognized as integral to securing a network is the Intrusion Prevention System (IPS), which is used to detect and prevent suspected malicious network traffic or behavior. However, an IPS is not just a ‘set-it-and-forget-it’ type of solution. This is because of the necessity of employing current Cisco IPS signatures, which are the lifeblood of the IPS and are essential for it to identify and block attacks against specific vulnerabilities or certain types of threats. Because new threats and vulnerabilities are constantly being discovered, the IPS signature database for an IPS-capable device needs to be kept current to maximize the level of protection that it can provide. If you already use Cisco IPS technology, then you might already be familiar how crucial it is to use the most current IPS signatures. Otherwise, the IPS solution cannot provide optimal protection against new threats and attacks. Cisco IPS owners with a Cisco IPS Services License understand this fact and can receive signature updates as they become available. Signature updates can be installed manually or downloaded and installed automatically using native Cisco IPS capabilities or management tools such as Cisco Security Manager. For those inclined to write their own signatures, Cisco has published documentation on how to write customer signatures for the IPS.

And while the signatures are the “lifeblood” of the IPS and keeping them current is paramount, it is also important to make sure that the underlying operating system is kept up to date on the sensor as well. The underlying operating system and engines decompose and analyze the traffic as it passes through the device. Things like protocol decoding, features, and evasion resistance are handled here. The engines work but do not alert without the signature set as the signatures provide the matching framework for an alert to fire. The same can be said about the signatures. They do not work without the engines. Each requires the other to function and therefore keeping them both current is important.

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