Windows Defender Zero-Day “RoguePlanet” Lets Attackers Gain SYSTEM Privileges

Gbhackers •Divya • June 10, 2026

A newly disclosed zero-day vulnerability dubbed “RoguePlanet” is affecting Microsoft Defender, allowing attackers to escalate privileges and obtain full SYSTEM-level access on vulnerable Windows machines. A security researcher recently published the issue under the alias “MSNightmare,” who released a proof-of-concept (PoC) exploit on GitHub. The vulnerability appears to affect both Windows 10 and Windows 11 […]

The full story

This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.

Nightmare-Eclipse Banned from GitHub and GitLab for Zero-Day Exploits The anonymous security researcher known as Nightmare-Eclipse has been banned from both GitHub and GitLab due to the release of multiple unpatched Windows vulnerabilities. GitHub terminated the account on May 25, 2026, after the researcher disclosed six exploits, including critical privilege escalation vulnerabilities like BlueHammer and YellowKey. Microsoft accused the researcher of violating coordinated vulnerability disclosure practices, leading to a public feud. Following the GitHub ban, Nightmare-Eclipse moved to GitLab, where they continued to release exploits until being suspended on May 26, 2026. The researcher has threatened further disclosures, claiming Microsoft has left them with no choice. The situation has sparked significant backlash within the cybersecurity community, highlighting tensions between researchers and corporate entities over vulnerability disclosure practices. 86 sources 68

Extracted Entities

Windows Defender Zero-Day “RoguePlanet” Lets Attackers Gain SYSTEM Privileges

The full story

Extracted Entities

Attack Types (1)

CWE Weaknesses (1)

MITRE ATT&CK (1)

Platforms (1)

Vulnerabilities (1)