Cisco Threat Research Blog

Cisco Talos is disclosing several vulnerabilities in ACD Systems’ Canvas Draw 5, a graphics-editing tool for Mac. The vulnerable component of Canvas Draw 5 lies in the handling of TIFF and PCX images. TIFF is a raster-based image format used in graphics editing projects, thus making it a very common file format that’s used in Canvas Draw. PCX was a popular image format with early computers, and although it’s been replaced by more sophisticated formats, it is still in use and fully supported by Canvas Draw.

In accordance with our coordinated disclosure policy, Cisco Talos worked with ACD Systems to ensure that these issues are resolved and that an update is available for affected customers.

Read more about these vulnerabilities here.

Marcin “Icewall” Noga of Cisco Talos discovered these vulnerabilities.

Executive Summary

Cisco Talos discovered two vulnerabilities that could allow remote code execution and memory disclosure at the kernel level in WIBU-SYSTEMS WibuKey. WibuKey is a USB key designed to protect software and intellectual properties. It allows the users to manage software license via USB key. A third vulnerability is located in userland and can be triggered remotely, as it’s located in the network manager.

In accordance with our coordinated disclosure policy, Talos worked with WIBU SYSTEMS to ensure that these issues are resolved and that an update is available for affected customers.

Read more >>>

Today, Talos is publishing a glimpse into the most prevalent threats we’ve observed between Jan. 18 and Jan. 25. As with previous roundups, this post isn’t meant to be an in-depth analysis. Instead, this post will summarize the threats we’ve observed by highlighting key behavioral characteristics, indicators of compromise, and discussing how our customers are automatically protected from these threats.

As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of the date of publication. Additionally, please keep in mind that IOC searching is only one part of threat hunting. Spotting a single IOC does not necessarily indicate maliciousness. Detection and coverage for the following threats is subject to updates, pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net.

Read More at Talosintelligence.com

TRU0125 — This is a JSON file that includes the IOCs referenced in this post, as well as all hashes associated with the cluster. The list is limited to 25 hashes in this blog post. As always, please remember that all IOCs contained in this document are indicators, and that one single IOC does not indicate maliciousness. See the Read More link above for more details.

This blog post was authored by John Arneson of Cisco Talos

Executive Summary

Cisco Talos once again spotted the Ursnif malware in the wild. We tracked this information stealer after Cisco’s Advanced Malware Protection (AMP) Exploit Prevention engine alerted us to these Ursnif infections. Thanks to AMP, we were able to prevent Ursnif from infecting any of its targets. The alert piqued our curiosity, so we began to dig a bit deeper and provide some recent IoCs related to this threat, which traditionally attempts to steal users’ banking login credentials and other login information. Talos has covered Ursnif in the past, as it is one of the most popular malware that attackers have deployed recently. In April, we detected that Ursnif was being delivered via malicious emails along with the IceID banking trojan.

Read more here

Today, Talos is publishing a glimpse into the most prevalent threats we’ve observed between Jan. 11 and Jan. 18. As with previous roundups, this post isn’t meant to be an in-depth analysis. Instead, this post will summarize the threats we’ve observed by highlighting key behavioral characteristics, indicators of compromise, and discussing how our customers are automatically protected from these threats.

As a reminder, the information provided for the following threats in this post is non-exhaustive and current as of the date of publication. Additionally, please keep in mind that IOC searching is only one part of threat hunting. Spotting a single IOC does not necessarily indicate maliciousness. Detection and coverage for the following threats is subject to updates, pending additional threat or vulnerability analysis. For the most current information, please refer to your Firepower Management Center, Snort.org, or ClamAV.net.

Read More at Talosintelligence.com

Reference
TRU0111-0118 – This is a JSON file that includes the IOCs referenced in this post, as well as all hashes associated with the cluster. The list is limited to 25 hashes in this blog post. As always, please remember that all IOCs contained in this document are indicators, and that one single IOC does not indicate maliciousness. See the Read More link above for more details.

This blog post was authored by Chris Marczewski

Cisco Talos has been tracking a series of Imminent RAT infections for the past two months following reported data from Cisco Advanced Malware Protection’s (AMP) Exploit Prevention engine. AMP successfully stopped the malware before it was able to infect the host, but an initial analysis showed a strong indication that stages exist before the deployment of the RAT. Surprisingly, the recovered samples showed no sign of Imminent RAT, but instead a commercial grade packer.

This was a series of attacks engineered to evade detection and frustrate analysis. From the outside, we have a commercially available, yet affordable packer called “Obsidium” that has been used in the past to protect the intellectual property of some legitimate software vendors. The payload results in a RAT called Imminent that has also been used previously for legitimate purposes. Imminent is a commercially available RAT that retails for $25 to $100, depending upon the size of the customer’s expected user base. While it is not intended for malicious use, in this case, its detection suggested otherwise.

Although a Potentially Unwanted Application (PUA) detection approach could suffice, not everyone enables blocking of PUAs. We have other technologies in place, such as the Exploit Prevention engine, that are well-suited to detecting such threats. We hope that after reading this research, you’ll have a better understanding of not only what it takes to investigate an attack using a complex packer, but also how AMP is equipped to stop such attacks that planned on successfully evading static detection or thwarting the benefits of dynamic analysis from a malware sandbox.

Read More

While Emotet has been around for many years and is one of the most well-known pieces of malware in the wild, that doesn’t mean attackers don’t try to freshen it up. Cisco Talos recently discovered several new campaigns distributing the infamous banking trojan via email. These new campaigns have been observed following a period of relatively low Emotet distribution activity, corresponding with the observance of Orthodox Christmas in certain geographic regions. These new malicious efforts involve sending victims malicious Microsoft Word attachments with embedded macros that download Emotet.

This latest strain has also gained the ability to check if the infected IP where the malicious email is being sent from is already blacklisted on a spam list. This could allow attackers to deliver more emails to users’ inboxes without any pushback from spam filters.

Read More >>

Vulnerability discovery and research by Jared Rittle and Carl Hurd of Cisco Talos.

Introduction

TP-Link recently patched three vulnerabilities in their TL-R600VPN gigabit broadband VPN router, firmware version 1.3.0. Cisco Talos publicly disclosed these issues after working with TP-Link to ensure that a patch was available. Now that a fix is out there, we want to take the time to dive into the inner workings of these vulnerabilities and show the approach we took with our proof-of-concept code.

Background

The TP-Link TL-R600VPN is a five-port small office/home office (SOHO) router. This device contains a Realtek RTL8198 integrated system on a chip. This particular chip uses an offshoot of the MIPS-1 architecture developed by Lexra. Except for a few proprietary instructions for handling unaligned load and store operations, these two instruction sets are essentially the same. The instructions that are not included in Lexra are LWL, SWL, LWR, and SWR. These proprietary instructions are often used when compiling a program for the more common MIPS-1 architecture and cause a segfault when encountered in Lexra. The knowledge of this key difference is imperative to assembling working code for the target.

For more information about Lexra MIPS and its differences with the MIPS-1 architecture, refer to ‘The Lexra Story‘ and the MIPS-1 patent filing.

Read more here

PyLocky is a family of ransomware written in Python that attempts to masquerade as a Locky variant. This ransomware will encrypt all files on a victim machine before demanding that the user pay a ransom to gain access to their decrypted files. To combat this ransomware, Cisco Talos is releasing a free decryption tool. Because our tool requires the capturing of the initial PyLocky command and control (C2) traffic of an infected machine, it will only work to recover the files on an infected machine where network traffic has been monitored. If the initial C2 traffic has not been captured, our decryption tool will not be able to recover files on an infected machine. This is because the initial callout is used by the malware to send the C2 servers information that it uses in the encryption process. 

For more information, check out the full post here.