110. Adversaries Use Maliciously Crafted .library-ms Files

Hello everyone! I'm sure everybody heard about CVE-2025-24054, which is related to NTLM hash disclosure via spoofing.

Check Point presented a report with an overview of how it's been exploited in-the-wild. The exploit is triggered with minimal user interaction, for example, selecting, inspecting, or performing any action other than opening or executing the file.

The threat actors use malicious .library-ms, which are distributed via phishing emails. Files with such extension are not very common, so we can hunt for file creation events:

event_type: "filecreate"

AND

file_path: "library-ms"

See you tomorrow!

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