Microsoft disclosed and patched several spoofing vulnerabilities across Windows and Exchange Server, including NTLM hash disclosure issues tracked as CVE-2025-24996, CVE-2025-59185, and CVE-2025-59244, a Windows NTLM spoofing flaw CVE-2025-21217, a Windows Themes spoofing bug CVE-2025-21308, a Windows Shell Link Processing spoofing issue CVE-2026-25185, and an older Microsoft Exchange Server spoofing vulnerability CVE-2021-24085. The advisories indicate a broad set of weaknesses that could let attackers disguise content or trigger credential exposure through trusted Windows components and enterprise messaging infrastructure.
The concentration of flaws around NTLM and user-facing file handling highlights continued risk from spoofing paths that can mislead users or disclose authentication material. For defenders, the updates underscore the need to prioritize Microsoft security patches for systems handling Windows authentication, shell link processing, themes, and Exchange workloads, especially where NTLM remains enabled and could be leveraged for credential theft or follow-on intrusion.

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7 events from the most recent confirmed update back to the earliest known activity.
Microsoft published a Security Update Guide entry for CVE-2026-25185, describing it as a Windows Shell Link Processing spoofing vulnerability.
Microsoft published a Security Update Guide entry for CVE-2025-59185, identifying it as an NTLM hash disclosure spoofing vulnerability.
Microsoft published a Security Update Guide entry for CVE-2025-59244, identifying it as an NTLM hash disclosure spoofing vulnerability.
Microsoft published a Security Update Guide entry for CVE-2025-24996, describing it as an NTLM hash disclosure spoofing vulnerability.
Microsoft published a Security Update Guide advisory for CVE-2025-21217, identifying it as a Windows NTLM spoofing vulnerability.
Microsoft published a Security Update Guide entry for CVE-2025-21308, describing it as a Windows Themes spoofing vulnerability.
Microsoft published a Security Update Guide entry for CVE-2021-24085, identifying it as a Microsoft Exchange Server spoofing vulnerability.
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