I published the following diary on isc.sans.edu: “New Example of XSL Script Processing aka ‘Mitre T1220‘”: Last week, Brad posted a diary about TA551. A few days later, one of our readers submitted another sample belonging to the same campaign. Brad had a look at the traffic so I decided
I published the following diary on isc.sans.edu: “Sensitive Data Shared with Cloud Services“: Yesterday was the data protection day in Europe. I was not on duty so I’m writing this quick diary a bit late. Back in 2020, the Nitro PDF service suffered from a data breach that impacted many
It’s very tempting and, honestly, I’m doing it from time to time… I search for pictures on the Internet and use them in my documents! Why it could be dangerous in some cases? Let’s put aside copyright issues (yes, some pictures might not be free of use) but focus on
I published the following diary on isc.sans.edu: “Another File Extension to Block in your MTA: .jnlp“: When hunting, one thing that I like to learn is how attackers can be imaginative at deploying new techniques. I spotted some emails that had suspicious attachments based on the ‘.jnlp’ extension. I’m pretty sure
I published the following diary on isc.sans.edu: “Powershell Dropping a REvil Ransomware“: I spotted a piece of Powershell code that deserved some investigations because it makes use of RunSpaces. The file (SHA256:e1e19d637e6744fedb76a9008952e01ee6dabaecbc6ad2701dfac6aab149cecf) has a very low VT score: only 1/59!. The technique behind RunSpaces is helpful to create new threads on the existing Powershell
A few weeks ago I wrote an ISC diary about a piece of malicious code that used ngrok.io to communicate with the C2 server. Just a quick reminder about this service: it provides a kind of reverse-proxy for servers or applications that people need to publish on the Internet. I
I published the following diary on isc.sans.edu: “Malicious Word Document Delivering an Octopus Backdoor“: Here is an interesting malicious Word document that I spotted yesterday. This time, it does not contain a macro but two embedded objects that the victim must “activate” (click on one of them) to perform the malicious activities.
I published the following diary on isc.sans.edu: “Malware Victim Selection Through WiFi Identification“: Last week, I found a malware sample that does nothing fancy, it’s a data stealer but it has an interesting feature. It’s always interesting to have a look at the network flows generated by malware samples. For
pfSense is a very popular free and open source firewall solution. It does not only provide classic firewall services but has plenty of features like VPN server or can offer DNS, DHCP, proxy services… and many more. pfSense is also proposed by some companies as a commercial service with support.
I published the following diary on isc.sans.edu: “Python Backdoor Talking to a C2 Through Ngrok“: I spotted a malicious Python script that implements a backdoor. The interesting behavior is the use of Ngrok to connect to the C2 server. Ngrok has been used for a while by attackers. Like most