23 July 2026
Reference: CVE-2025-24054
1. What is being reported?
Security researchers have identified a vulnerability in the way Windows handles file names or paths during network authentication using NTLM. This weakness could let an attacker impersonate or spoof devices or users on your network by manipulating file information.
2. What this means in plain English
For a small organisation, this means that if your systems use Windows with NTLM authentication, an attacker might be able to pretend to be a trusted device or user. This could lead to unauthorised access or disruption of your network communications.
3. Could this affect a small business?
Small businesses using Windows computers, especially those running Microsoft Office or Teams and connected to a network, could be affected. If your setup includes plugins or services that rely on NTLM authentication, you should be cautious. Organisations not using Windows or NTLM are less likely to be impacted.
4. What to do now
- Check with your IT provider whether your Windows systems are affected by this vulnerability.
- Ensure all Windows updates and patches are applied promptly as recommended by Microsoft.
- Review your network authentication settings and consider stronger authentication methods if possible.
- Be alert for unusual network activity or unexpected file access requests and report them to your IT support.
5. Ask your IT provider
Can you confirm if our Windows systems are vulnerable to CVE-2025-24054 and what steps are being taken to protect us?
6. Bottom line
Keep your Windows systems updated and consult your IT support to reduce the risk of attackers spoofing your network.
Information based on CISA KEV, NVD, and reputable security reporting.