Yara CTF, Blackhat 2015

Welcome and good luck on the CTF!

Password: “Go forth and hack!!##one1″, no quotes.

PM_Yara_CTF_2015

One of the challenges is to write an exploit, so please exercise responsible disclosure on this one! We will be working with the developers to get the code patched ASAP!

Please note: Challenge #4 contains a typo, it needs a Yara rule, not a key. Sorry for the error.

These Are Not The (CryptoLocker) Resumes You’re Looking For

For a long time, attackers have used .zip files in order to carry their bad stuff to organizations. Typically attackers include the malware in an .exe or screensaver file in the .zip , but we’ve noticed attackers trying to tell a different story in a recent wave of attacks.  Here’s a screenshot of one of the emails:

FIgure 1 -- Phishing email

FIgure 1 — Phishing email

Once opened, the user is prompted to download a .zip file. We can see this in the iframe of the html file inside, as well as the .zip file that is downloaded. [Read more…]

Forget About IOCs… Start Thinking About IOPs!

For those who may have lost track of time, it’s 2015, and phishing is still a thing. Hackers are breaking into networks, stealing millions of dollars, and the current state of the Internet is pretty grim.

We are surrounded with large-scale attacks, and as incident responders, we are often overwhelmed, which creates the perception that the attackers are one step ahead of us. This is how most folks see the attackers, as being a super villain who only knows evil, breathes evil, and only does new evil things to trump the last evil thing.

This perception leads to us receiving lots of questions about the latest attack methods. Portraying our adversaries as being extremely sophisticated, powerful foes makes for a juicy narrative, but the reality is that attackers are not as advanced as they are made out to be.

[Read more…]

Disrupting an Adware-serving Skype Botnet

In the early days of malware, we all remember analyzing samples of IRC botnets that were relatively simple, where the malware would connect to a random port running IRC, joining the botnet and waiting for commands from their leader. In this day and age, it’s slightly different. Whereas botnets previously had to run on systems that attackers owned or had compromised, now bots can run on Skype and other cloud-based chat programs, providing an even lower-cost alternative for attackers.

[Read more…]

Updated Dyre, Dropped by Office Macros

Whenever attackers make a shift in tactics, techniques, and protocol (TTP), we like to make note of it to help both customers and the rest of the Internet community. We recently analyzed a sample that started out appearing to be Dridex, but quickly turned into a headache leading to Dyre that featured some notable differences to past Dyre samples. One PhishMe user was targeted to their personal account, and here’s a copy of the phishing email:

Figure 1 -- Phishing email

Figure 1 — Phishing email

Once opened, we’re presented with the very familiar story of “please enable this macro so you can get infected”. This time, they do give a few more instructions to the user, saying that the data is “encoded” and macros need to be enabled to read the text.

[Read more…]

Detecting a Dridex Variant that Evades Anti-virus

Attackers constantly tweak their malware to avoid detection. The latest iteration of Dridex we’ve analyzed provides a great example of malware designed to evade anti-virus, sandboxing, and other detection technologies.

How did we get our hands on malware that went undetected by A/V? Since this malware (like the majority of malware) was delivered via a phishing email, we received the sample from a user reporting the phishing email using Reporter. [Read more…]

The Return of NJRat

NJRat is a remote-access Trojan that has been used for the last few years. We haven’t heard much about NJRat since April 2014, but some samples we’ve recently received show that this malware is making a comeback. ( For some background on NJRat,  a 2013 report from Fidelis Cybersecurity Solutions at General Dynamics detailed indicators, domains, and TTP’s in conjunction with cyber-attacks using NJRat.) [Read more…]

Dridex Code Breaking – Modify the Malware to Bypass the VM Bypass

Post Updated on March 25

The arrival of spring brings many good things, but it’s also prime season for tax-themed phishing emails. A partner of ours recently reported an email with the subject “Your Tax rebate” that contained an attachment with Dridex and password-protected macros to hinder analysis. If you read this blog, this story should sound familiar, but this particular strain took new precautions, such as adding a longer password and using VM detection inside of the code. [Read more…]

Decoding ZeuS Disguised as an .RTF File

While going through emails that were reported by our internal users using Reporter, I came across a particularly nasty looking phishing email that had a .doc attachment. At first when I detonated the sample in my VM, it seemed that the attackers weaponized the attachment incorrectly. After extracting and decoding the shellcode, I discovered a familiar piece of malware that has been used for some time. [Read more…]