The legacy NTLM (NT LAN Manager) authentication protocol, while still prevalent in Windows devices, poses significant cybersecurity risks. Enabled by default, NTLM can become a vulnerability, potentially exposing your system passwords during malware attacks. Attackers often capitalize on these weaknesses using sophisticated man-in-the-middle (MitM) techniques, making it vital for users to take proactive steps in securing their NTLM credentials.
Understanding NTLM Threats
NTLM operates by converting your password into a hashed format, allowing verification without transmitting the actual password over the network. However, this method is susceptible to attacks. If malware infiltrates your system, your password could be compromised easily.
Highlighting recent vulnerabilities, security researchers at Check Point detailed the “CVE-2025-24054” flaw that has led to ongoing cyber threats targeting sensitive data primarily in governmental and corporate sectors across Poland and Romania. Attackers are deploying various techniques, including pass-the-hash (PtH), rainbow table, and relay attacks, primarily aiming at high-level administrative accounts.
While these attacks are often directed at organizations, individual users are not immune. Even a simple interaction with a malicious file can result in password exposure. Therefore, it’s crucial to ensure that your Windows system is regularly updated; Microsoft has introduced a security update aimed at thwarting this particular type of exploit.
1. Disable NTLM Authentication Using PowerShell
To fortify your defense against NTLM-related risks, begin by disabling NTLM authentication through PowerShell. Follow these steps:
- Launch PowerShell in administrator mode.
- Execute the following command to block NTLM usage over SMB (Server Message Block):
Set-SMBClientConfiguration -BlockNTLM $true
Confirm the modification by pressing A for yes. By blocking NTLM over SMB, you significantly reduce vulnerabilities to PtH and relay attacks, although it may impact older devices that rely on NTLM.
If you experience compatibility issues, revert the setting using:
Set-SMBClientConfiguration -BlockNTLM $false
2. Switch to NTLMv2 in the Registry Editor
Transitioning from the older NTLM to the more secure NTLMv2 is crucial for better security. Begin by backing up your registry and opening the Registry Editor as an administrator. Navigate to the following path:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
Locate or create the LmCompatibilityLevel DWORD value. Set it to “3”, “4”, or “5” to ensure only NTLMv2 responses are sent, effectively blocking NTLMv1.
Next, adjust the following registry path:
COMPUTER\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanWorkstation\Parameters
Ensure the RequireSecuritySignature DWORD is set to “1”.This adjustment will mandate security signing for SMB connections, adding another layer of protection against credential theft.
3. Enable Cloud Protection in Windows Security
For those who prefer not to modify the registry, leveraging the built-in Windows Security feature can provide substantial protection against online threats. Access this feature by navigating to Virus & threat protection > Manage settings > Cloud-delivered protection.
4. Exploring Additional Security Measures
In addition to the aforementioned steps, consider these further recommendations by Microsoft to bolster your defenses against NTLM credential theft:
- Avoid suspicious links: Many NTLM-related threats propagate through clickbait or malicious links. Even if Windows Security flags these threats, exercise caution to mitigate exposure.
- Regularly update your system: Consistently check for and apply Windows updates to protect against newly discovered vulnerabilities.
- Utilize Multi-Factor Authentication (MFA): Implementing MFA can provide an additional layer of protection, making unauthorized access substantially more difficult.
- Educate yourself and others: Being aware of social engineering tactics and phishing schemes can help prevent accidental exposure.
Taking these critical steps will significantly reduce the chances of your Windows NTLM credentials being compromised, enhancing overall system security.
Related Articles:
Transforming Windows 11 into Windows 7: Enhanced Performance and Functionality
8:00
Is X’s New Encrypted Messaging a Smart Move for Security or Just a Mirage?
7:54
Troubleshooting the “Don’t Cover The Earphone Area” Warning on Android Devices
15:28
Leave a Reply