April kicked off with a 1:292 rate of malware encounters and closed with a rate of 1:315. Highest peak day was April 20 when the rate reached 1:177. Lowest was April 4 at 1:338. The median rate of web malware encounters in April 2014 was 1:292, representing a slight improvement over the median of 1:260 requests in March but still worse than the median of 1:341 requests in February.
This post is co-authored by Andrew Tsonchev, Jaeson Schultz, Alex Chiu, Seth Hanford, Craig Williams, Steven Poulson, and Joel Esler. Special thanks to co-author Brandon Stultz for the exploit reverse engineering.
Silverlight exploits are the drive-by flavor of the month. Exploit Kit (EK) owners are adding Silverlight to their update releases, and since April 23rd we have observed substantial traffic (often from Malvertising) being driven to Angler instances partially using Silverlight exploits. In fact in this particular Angler campaign, the attack is more specifically targeted at Flash and Silverlight vulnerabilities and though Java is available and an included reference in the original attack landing pages, it’s never triggered.
As of May 1, 2014, we can confirm Cisco customers have been targets of this attack. For the latest coverage information and additional details see our new post on the VRT blog.
Protecting company critical assets is a continuing challenge under normal threat conditions. The disclosure of zero-day exploits only makes the job of IT security engineers that much harder. When a new zero-day vulnerability was announced on April 26, 2014 for Microsoft Internet Explorer, corporate security organizations sprang into action assessing the potential risk and exposure, drafting remediation plans, and launching change packages to protect corporate assets.
Some companies however, rely on Managed Security Services to protect those same IT assets. As a Cisco Managed Security services customer, the action was taken to deploy updated IPS signatures to detect and protect the companies critical IT assets. In more detail, the IPS Signature team, as a member of the Microsoft Active Protections Program (MAPP), developed and released Cisco IPS signature 4256/0 in update S791 and Snort rules 30794 & 30803 were available in the ruleset dated 4-28-2014. The Cisco Managed Security team, including Managed Threat Defense, received the update as soon as it became available April 28th. Generally, Cisco Managed Security customers have new IPS signature packs applied during regularly scheduled maintenance windows. In the event of a zero-day, the managed security team reached out to customers proactively to advise them of the exploit and immediately were able to apply signature pack updates to detect and protect customer networks.
While corporate security organizations must still assess ongoing risks and direct overall remediations to protect corporate data, Cisco can take the actions to provide security visibility into the targeted attacks, increase protection with fresh signatures, and reduce risk profile for the corporate InfoSec program.
For more detail on the vulnerability, please see Martin Lee’s blog post.
More details about this exploit and mitigation information can be found on the following links:
- Cisco IPS Signature S791
- Snort Ruleset
- Cisco IPS Sub-Signature 4256-1
- Cisco IntelliShield Alert 33961
For additional information about Cisco Managed Security solutions please refer to the following links and contact your Cisco Services sales representative:
Update 5-1-2014: We can confirm Cisco customers have been targets of this attack. For the latest coverage information and additional details see our new post on the VRT blog.
The recent discovery of a new Internet Explorer zero-day exploit underlines how exposed web browsers are to vulnerabilities for which a patch is yet to be released. Cisco is aware of the issue and is releasing IPS signature 4256-0 and Snort signatures 30794, 30803 to detect the exploitation of this vulnerability. You can read more details from Cisco here.
Anyone can purchase an exploit pack (EP) license or rent time on an existing EP server. The challenge for threat actors is to redirect unsuspecting web browsing victims by force to the exploit landing page with sustained frequency. Naturally, like most criminal services in the underground, the dark art of traffic generation is a niche specialty that must be purchased to ensure drive-by campaign success. For the past year we have been tracking a threat actor (group) that compromises legitimate websites and redirects victims to EP landing pages. Over the past three months we observed the same actor using malvertising – leveraging content delivery networks (CDNs) to facilitate increased victim redirection – as part of larger exploit pack campaigns. Read More »