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Writeup : https://github.com/califio/publications/blob/main/MADBugs/CVE-2026-4747/write-up.md

If you set LmCompatibilityLevel to 5 a couple years back and called it done, there's a good chance NTLMv1 is still running in your environment. Not because the setting doesn't work. Because it doesn't work the way you think it does.

This isn't just aimed at people who never fully switched to Kerberos. It's also for the ones who are pretty sure they did.

For people not deep into auth protocols: NTLMv1 and NTLMv2 are both considered unsafe today. NTLMv1 especially. It uses DES encryption, which with a weak password can be cracked in seconds. And because NTLM never sends your actual password (challenge-response, the hash gets passed not the plaintext), it's also wide open to pass-the-hash. An attacker intercepts the hash and reuses it to authenticate as you. Responder is the tool that makes this trivial and it's been around forever.Silverfort's research puts 64% of authentications in AD environments still on NTLM.

Here's the actual problem with the registry fix. LMCompatibilityLevel is supposed to tell your DCs to reject NTLMv1 traffic and require NTLMv2 or Kerberos instead. Sounds reasonable. But enforcement runs through the Netlogon Remote Protocol (MS-NRPC), the mechanism application servers use to forward auth requests to your domain controllers. There's a structure in that protocol called NETLOGON_LOGON_IDENTITY_INFO with a field called ParameterControl. That field contains a flag that can explicitly request NTLMv1, and your DC will honor it regardless of what Group Policy says.

The policy controls what Windows clients send. It has no authority over what applications request on the server side. Any third party or homegrown app that hasn't been audited can still be sending NTLMv1 traffic and you'd have no idea.

Silverfort built a POC to confirm this. They set the ParameterControl flag in a simulated misconfigured service and forced NTLMv1 authentications through a DC that was configured to block them. Worked. They reported it to Microsoft, Microsoft confirmed it but didn't classify it as a vulnerability. Their response was to announce full removal of NTLMv1 starting with Windows Server 2025 and Windows 11 24H2. So that's something, atleast.

If you're not on those versions, you're still exposed and there's no patch coming.

What you can do right now: turn on NTLM audit logging across your domain. Registry keys exist to capture all NTLM traffic so you can actually see what's authenticating how. From there, map every app using NTLM, whether primary or as a fallback, and look specifically for anything requesting NTLMv1 messages. That's your exposure.

The University of North Georgia is one of the lesser known of the nation's senior military colleges (SMCs). But last week it beat out all the other five SMCs—and two of the elite service academies—in a capture-the-flag hacker contest staged at the Pentagon's Cyber Workforce Summit.

The contest was designed by specialists from the Air Force Research Laboratory to be operationally realistic. In the first round, teams had to geo-locate a targeted individual through his devices and apps, prevent him from getting warning messages, and then call in an air strike to kill him.

More details and quotes from UNG students—plus the team from The Citadel they bested in the final—in my latest story.

Axios is one of the most used npm packages which just got hit by a supply chain attack. Malicious versions of Axios (1.14.1 and 0.30.4) hit the npm registry yesterday. They carry a malware dropper called plain-crypto-js@4.2.1. If you ran npm install in the last 24 hours, check your lockfile. Roll back to 1.14.0 and rotate every credential that was in your environment. Currently, as of now, npmjs has removed the compromised versions of axios package along with the malicious plain crypto js package. Live updates + info linked.

Due to the increasing trend of OAuth abuse in phishing and most users' lack of understanding between Device Code and OAuth App Consent phishing, I just added them to the PhishU Framework. Now with a quick, two-step process red teams and internal orgs can leverage the templates to train users for this very real-world attack.

Check out the blog for details at https://phishu.net/blogs/blog-microsoft-entra-device-code-phishing-phishu-framework.html if interested!

Write up of a vulnerability chain from a recent SaaS pen test. Two medium-severity findings (file upload bypass and stored XSS) chained together for full admin account creation.

The target had CSP restricting script sources to self, CORS locked down, and CSRF tokens on forms. All functioning correctly. The chain bypassed everything by staying same-origin the entire way.

The file upload had no server-side validation (client-side accept=".pdf" only), so we uploaded a JS payload. It got served back from the app's own download endpoint on the same origin. The stored XSS in the admin inbox messaging system loaded it via an <img onerror> handler that fetched the payload and eval'd it. The payload created a backdoor admin account using the admin's session cookie.

CSP didn't block it because the script was hosted same-origin via the upload. CORS irrelevant since nothing crossed an origin boundary. CSRF tokens didn't matter because same-origin JS can read the DOM and grab them anyway.

Full write up with attack steps, code, and screenshots: https://kurtisebear.com/2026/03/28/chaining-file-upload-xss-admin-compromise/

Also built a Docker lab that reproduces the exact chain with the security controls in place. PHP app, both vulns baked in, admin + user accounts seeded. Clone and docker-compose up: https://github.com/echosecure/vuln-chain-lab

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