On Wednesday, a phishing message made its way into our handler inbox that contained a fairly typical low-quality lure, but turned out to be quite interesting in the end nonetheless. That is because the accompanying credential stealing web page was dynamically constructed using React and used a legitimate e-mail service for credential collection.

[This is a Guest Diary by Joseph Gruen, an ISC intern as part of the SANS.edu BACS program]

And another XWorm[1] wave in the wild! This malware family is not new and heavily spread but delivery techniques always evolve and deserve to be described to show you how threat actors can be imaginative! This time, we are facing another piece of multi-technology malware.

CrushFTP is a Java-based open source file transfer system. It is offered for multiple operating systems. If you run a CrushFTP instance, you may remember that the software has had some serious vulnerabilities: CVE-2024-4040 (the template-injection flaw that let unauthenticated attackers escape the VFS sandbox and achieve RCE), CVE-2025-31161 (the auth-bypass that handed over the crushadmin account on a silver platter), and the July 2025 zero-day CVE-2025-54309 that was actively exploited in the wild.

In 2010, OWASP added "Unvalidated Redirects and Forwards" to its Top 10 list and merged it into "Sensitive Data Exposure" in 2013 [owasp1] [owasp2]. Open redirects are often overlooked, and their impact is not always well understood. At first, it does not look like a big deal. The user is receiving a 3xx status code and is being redirected to another URL. That target URL should handle all authentication and access control, regardless of where the data originated.

A few days ago I wrote a diary called "Malicious Script Delivering More Maliciousness"[1]. In the malware infection chain, there was a JPEG picture that embedded the last payload delimited with "BaseStart-" and "-BaseEnd" tags.

In 2022 (time flies!), I wrote a diary about the 32-bits VS. 64-bits malware landscape[1]. It demonstrated that, despite the growing number of 64-bits computers, the "old-architecture" remained the standard. In the SANS malware reversing training (FOR610[2]), we quickly cover the main differences between the two architectures. One of the conclusions is that 32-bits code is still popular because it acts like a comme denominator and allows threat actors to target more Windows computers. Yes, Microsoft Windows can smoothly execute 32-bits code on 64-bits computers. It is still the case in 2026? Did the situation evolved?

Today, Apple released updates for all of its operating systems (iOS, iPadOS, macOS, tvOS, watchOS, and visionOS). The update fixes 71 distinct vulnerabilities, many of which affect multiple operating systems. Older versions of iOS, iPadOS, and macOS are also updated.

WSL or “Windows Subsystem Linux”[1] is a feature in the Microsoft Windows ecosystem that allows users to run a real Linux environment directly inside Windows without needing a traditional virtual machine or dual boot setup. The latest version, WSL2, runs a lightweight virtualized Linux kernel for better compatibility and performance, making it especially useful for development, DevOps, and cybersecurity workflows where Linux tooling is essential but Windows remains the primary operating system. It was introduced a few years ago (2016) as part of Windows 10.