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New Windows RasMan zero-day flaw gets free, unofficial patches. Free unofficial patches are available for a new Windows zero-day vulnerability that allows attackers to crash the Remote Access Connection Manager (RasMan) service. RasMan is a critical Windows system service that starts automatically, runs in the background with SYSTEM-level privileges, and manages VPN, Point-to-Point Protocol over Ethernet (PPoE), and other remote network connections. ACROS Security (which manages the 0patch micropatching platform) discovered a new denial-of-service (DoS) flaw while looking into CVE-2025-59230, a Windows RasMan privilege escalation vulnerability exploited in attacks that was patched in October. The DoS zero-day has not been assigned a CVE ID and remains unpatched across all Windows versions, including Windows 7 through Windows 11 and Windows Server 2008 R2 through Server 2025. As the researchers found, when combined with CVE-2025-59230 (or similar elevation-of-privileges flaws), it allows attackers to execute code by impersonating the RasMan service. However, that attack only works when RasMan is not running. The new flaw provides the missing puzzle piece, enabling threat actors to crash the service at will and opening the door to privilege escalation attacks that Microsoft thought it had closed. Unprivileged users can exploit the zero-day to crash the RasMan service due to a coding error in how it processes circular linked lists. When the service encounters a null pointer while traversing a list, it attempts to read memory from that pointer rather than exiting the loop, causing a crash. ACROS Security now provides free, unofficial security patches for this Windows RasMan zero-day via its 0Patch micropatching service for all affected Windows versions until Microsoft releases an official fix. To install the micropatch on your device, you have to create an account and install the 0Patch agent. Once launched, the agent will automatically apply the micropatch without requiring a restart unless a custom patching policy blocks it. "We alerted Microsoft about this issue; they will likely provide an official patch for still-supported Windows versions in one of future Windows updates," ACROS Security CEO Mitja Kolsek said today. "As always, we included these 0day patches in our FREE plan until the original vendor has provided their official patch." A Microsoft spokesperson was not immediately available for comment when contacted by BleepingComputer earlier today. Break down IAM silos like Bitpanda, KnowBe4, and PathAI Broken IAM isn't just an IT problem - the impact ripples across your whole business. This practical guide covers why traditional IAM practices fail to keep up with modern demands, examples of what "good" IAM looks like, and a simple checklist for building a scalable strategy.

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VULNERABILITIES // Unofficial Patches Released for Windows RasMan Zero-Day Vulnerability

ACROS Security has issued free unofficial patches for a newly discovered Windows zero-day vulnerability affecting the Remote Access Connection Manager (RasMan) service.

The vulnerability allows attackers to crash the RasMan service, which is critical for managing VPN and remote network connections, potentially leading to privilege escalation attacks.

This flaw affects all Windows versions, from Windows 7 to Windows 11, and Windows Server 2008 R2 through Server 2025, remaining unpatched by Microsoft.

The vulnerability is due to a coding error involving circular linked lists, where a null pointer causes the service to crash instead of exiting the loop.

ACROS Security's 0patch micropatching platform offers these patches until Microsoft releases an official fix, requiring users to install the 0Patch agent for automatic updates.

Microsoft has been informed of the issue and is expected to provide an official patch in future updates, but no immediate comment was available.

Organizations are advised to implement the unofficial patches to mitigate the risk until an official solution is provided by Microsoft.