PHP2Shell: Critical RCE Vulnerabilities Affect a Large Majority of Web Servers
Update Oct 22 2026: New sections were added for “Observed Threat Activity and Indicators” and “Mitigations and Recommendations.”

Update Oct 22 2026: New sections were added for “Observed Threat Activity and Indicators” and “Mitigations and Recommendations.”

With contributions from James Rodriguez, Gus Stamatinos, and Timmy Lister.

On Sept 27, Citrix released patches for two critical vulnerabilities being exploited in the wild. Based on current information, we confirm there has been no exposure or impact to LevelBlue or our clients. CISA has already added these vulnerabilities to the Known Exploited Vulnerabilities (KEV) list.

Microsoft's Self-Service Password Reset (SSPR) portal is a legitimate feature designed to let users recover their accounts without calling the helpdesk. As it turns out, it also tells you quite a lot about the accounts in a tenant — whether they exist, what authentication methods they have registered, and in some cases, which ones are likely administrators. This post covers what the portal leaks, why it matters from both sides, and what defenders can do about it.

(Edit - Sept 17, 2026): The originally released PoC had issues that broke exploitation. That PoC has been revised by the author. We have reviewed the revised version of the exploit and have validated that it now functions as expected in our lab. We have added a section at the end of our original article discussing this update and our results.

In our previous blog, we explored a series of disclosures from the leak persona Nightmare-Eclipse that focused heavily on Microsoft's ecosystem, including Windows Defender, Cloud Files, and core operating system functionality.

This is a collaborative follow-up to our original post, developed jointly with Emmanuel C., a security researcher not affiliated with LevelBlue, who contributed additional infrastructure and tooling findings based on an analysis of the same GitHub staging account.

A cyber incident affecting a small UK electricity generator in July 2026 resulted in several days of operational unavailability and triggered a government and NCSC response. UK authorities confirmed that the event posed no threat to the wider grid and caused no customer outages. Media reporting described the affected asset as a small gas-fired peaking plant of approximately 15 MW, although the operator, location, technical architecture, and exact attack path remain undisclosed.

In Part 4, we stole every document from every index, planted a rogue superuser account, created credential-independent API keys, and planted three persistence mechanisms that survive password rotations. Everything was logged. Now we answer two final questions: how much worse could it get, and how do we put everything back?

We have access through port 9200. We have code execution through port 5601. Reconnaissance is complete, CVEs have been exploited, and Kibana has been compromised. Over the past three posts, we proved that we could get in. Now we prove what happens after.

In Parts 1 and 2, every command targeted port 9200. Every exploit, every reconnaissance query, every credential test hit the Elasticsearch REST API directly. But Elasticsearch rarely operates alone. Sitting alongside it on most deployments is Kibana, the visualization and management interface, quietly serving dashboards on port 5601 with its own API surface, plugin architecture, and history of critical vulnerabilities.

The LevelBlue OpsCTI Team recently identified a large-scale phishing campaign leveraging a new social engineering method to deploy unauthorized ConnectWise ScreenConnect clients. Rather than relying on conventional phishing pages, the campaign recreates convincing software update and installation alerts by impersonating the Microsoft Store and Apple App Store while reproducing the look and behavior of trusted applications through dynamic modal dialogs and other interactive web elements. The campaign impersonates trusted software and services, including Google Meet, Adobe Acrobat, Microsoft Teams, Zoom, Docusign, Secure Access Manager, Blue Mountain, Paperless Post, and other popular applications.

In Part 1, we went from a single open port to a complete map of the target. Version, topology, indices, secrets, credentials, privilege structure — all of it documented, all of it ready to be weaponized. Reconnaissance is finished. Now we find out what breaks.

You are mid-engagement. Nmap finishes its sweep and port 9200 lights up on a host. Elasticsearch. You know it matters. You know the client's logging pipeline, search infrastructure, or analytics platform probably flow through it. But what do you actually know about this cluster? Right now, nothing. No version, no configuration, no indication of whether it is locked down or wide open.

You have almost certainly interacted with Elasticsearch today. The search bar on your company's internal wiki. The autocomplete on the e-commerce site where you ordered lunch. The log aggregation dashboard your SOC team stares at for eight hours straight. The recommendation engine that just served you this article. Elasticsearch is the invisible infrastructure behind modern search, and it processes some of the most sensitive data an organization possesses, including access logs, customer records, financial transactions, and authentication events. It knows where your users click, what they search for, and when they log in.

Following GreenPlasma, YellowKey and MiniPlasma, as well as RoguePlanet and GreatXML, the Nightmare-Eclipse disclosure actor has published LegacyHive, its latest Windows proof-of-concept (PoC) released shortly after Microsoft's July 2026 Patch Tuesday.

Coordinated vulnerability disclosures operate on a straightforward premise: the affected vendor is notified first, given a defined window to remediate, and public disclosure follows.

Vexed researcher Nightmare-Eclipse (aka Chaotic Eclipse, Dead Eclipse, and MSNightmare) released his ninth unpatched Windows vulnerability called LegacyHive. This latest bug drop is a Local Privilege Escalation (LPE) vulnerability affecting Windows User Profile, a component responsible for loading and unloading Windows user profiles. When exploited, LegacyHive can enable attackers to load other users’ hives and gain access to application data and Windows Explorer history, among others.

You're browsing a legitimate small business website. Before the page loads, a familiar Cloudflare box appears: "Verify you are human." It asks you to open Terminal, paste a code, and press Enter. You've seen this before. You follow the steps. The page loads normally.

The LevelBlue Managed Threat Research team investigated a security alert in a customer environment involving a malicious ZIP file containing a Windows shortcut (.lnk) used for initial execution. When triggered, the LNK file executes a hidden PowerShell command that downloads a legitimate node.exe binary and deploys a NodeJS-based backdoor. The malware also uses the EtherHiding technique, leveraging the TON blockchain to retrieve its command-and-control (C2) address.