Microsoft Windows NTLM Hash Disclosure Spoofing Vulnerability

External control of file name or path in Windows NTLM allows an unauthorized attacker to perform spoofing over a network.

CheckOps priority index

6.9/10 Patch within 7 days

Severity6.5

Probability6.2

Exploitation4/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 62.3% higher than 99.2% of CVEs

CVSS 3.1 6.5 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:

Exploited for 565 days 17 Apr 2025

CISA due date 08 May 2025 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

KEV catalog (CISA)17 Apr 2025
Exploited in EUVD (ENISA)17 Apr 2025
Used by ransomwareno
EPSS above 10 %62.3%
No account, over the networkyes

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Affected products

Windows Server 2022, 23H2 Edition (Server Core installation)Windows Server 2008 R2 Service Pack 1 (Server Core installation)Windows Server 2019 (Server Core installation)Windows Server 2008 R2 Service Pack 1Windows 10 Version 1809Windows 10 Version 1507Windows Server 2012 R2Windows 11 version 22H3Windows Server 2012 (Server Core installation)Windows Server 2019Windows 10 Version 1607Windows 11 Version 23H2Windows Server 2016 (Server Core installation)Windows Server 2012Windows Server 2012 R2 (Server Core installation)Windows 11 version 22H2Windows Server 2025Windows Server 2025 (Server Core installation)Windows 10 Version 22H2Windows 10 Version 21H2Windows 11 Version 24H2Windows Server 2016Windows Server 2022Windows

Affected versions

10.0.25398.0 <10.0.25398.1486
6.1.7601.0 <6.1.7601.27618
10.0.17763.0 <10.0.17763.7009
10.0.10240.0 <10.0.10240.20947
6.3.9600.0 <6.3.9600.22470
10.0.22631.0 <10.0.22631.5039
6.2.9200.0 <6.2.9200.25368
10.0.14393.0 <10.0.14393.7876
10.0.22621.0 <10.0.22621.5039
10.0.26100.0 <10.0.26100.3476
10.0.19045.0 <10.0.19045.5608
10.0.19044.0 <10.0.19044.5608

Weaknesses (CWE)

CWE-73

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

11 Mar 2025
Published
17 Apr 2025
Exploitation reported (ENISA)
17 Apr 2025
Added to the KEV catalog
08 May 2025
CISA remediation due date
14 Oct 2026
EPSS peak: 62.3%

References

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