Centurion: Bring Your Own Execution Environment
Writing my own virtualized loader is something I’ve been wanting to do since I first read Microsoft’s deep dive on FinFisher’s multi-layered VM obfuscation back in 2018. FinFisher didn’t just use one layer of protection, it implemented a custom virtual machine with 32 opcode handlers, wrapped that in spaghetti code and anti-debug checks, and then buried a second VM […]
When Encryption Isn’t Really Encryption
Discovery During a recent network security assessment, we were working on an environment that was well-hardened – Patching was current, password policies were strong, and network segmentation was in place. So, as part of our enumeration of all network assets, we started looking for default credentials and this led us to multiple Canon enterprise printers […]
Your Login Page Is Lying: What AI Agents Find When They Read Your Frontend
TL;DR: Single-page applications ship their entire frontend codebase to every visitor, including unauthenticated ones. Even a login page with no visible functionality delivers JavaScript bundles containing route definitions, API endpoint URLs, authentication logic, data models, and sometimes hardcoded secrets. As part of Guard’s continuous penetration testing, we use AI-assisted tooling to extract this information and […]
500,000 Vulnerabilities, 14 That Matter: How Exploit Chain Analysis Cuts Through the Noise
When 500,000 Findings Hide 14 Real Threats Modern enterprises ingest vulnerability data from dozens of sources: endpoint detection and response platforms, vulnerability scanners, cloud security posture tools, container image scanners. A large organization can easily accumulate hundreds of thousands of individual findings. The standard response is to sort by CVSS score, filter for criticals, and […]
Reflecting on Your Tier Model: CVE-2025-33073 and the One-Hop Problem
The False Sense of Security SMB signing on domain controllers has become standard practice across most Active Directory environments. But this hardening may have created a false sense of security. CVE-2025-33073 changes the calculus by removing the prerequisite of admin access, enabling NTLM relay attack Active Directory exploitation through unconstrained delegation. Domain controllers enforce SMB […]
Which Came First: The System Prompt, or the RCE?
During a recent penetration test, we came across an AI-powered desktop application that acted as a bridge between Claude (Opus 4.5) and a third-party asset management platform. The idea is simple: instead of clicking through dashboards and making API calls, users just ask the agent to do it for them. “How many open tickets do […]
Azure APIM Signup Bypass: 97.9% of Developer Portals Still Exploitable Anonymously and from the Internet
The Azure APIM signup bypass is a critical vulnerability affecting 97.9% of internet-facing Developer Portals. Azure API Management (APIM) exposes APIs to external consumers through a Developer Portal, the interface where developers self-register, obtain API keys, and make API calls. The default APIM configuration ships with Basic Authentication enabled as the identity provider and the […]
When HttpOnly Isn’t Enough: Chaining XSS and GhostScript for Full RCE Compromise
What started as a standard cross-site scripting vulnerability in a document processing platform turned into a full administrative takeover of the application and, ultimately, remote code execution on the underlying server. The HttpOnly flag protected the session cookie from Javascript, but did the application keep it safe? During a recent assessment of a document processing […]
Et Tu, RDP? Detecting Sticky Keys Backdoors with Brutus and WebAssembly
Everyone knows that one person on the team who’s inexplicably lucky, the one who stumbles upon a random vulnerability seemingly by chance. A few days ago, my coworker Michael Weber was telling me about a friend like this who, on a recent penetration test, pressed the shift key five times at an RDP login screen […]
When Proxies Become the Attack Vectors in Web Architectures
Many Reverse proxy attack vectors expose a flawed assumption in modern web architectures that backends can blindly trust security-critical headers from upstream reverse proxies. This assumption breaks down because HTTP RFC flexibility allows different servers to interpret the same headers in fundamentally different ways, creating exploitable gaps that attackers are increasingly targeting. I want to […]