---
title: "CVE-2024-43451: Microsoft Windows NTLMv2 Hash Disclosure Spoofing Vulnerability"
url: https://erroneo.us/security/cve/CVE-2024-43451/
description: "CVE-2024-43451 (Microsoft Windows): Exploited in the wild (CISA KEV). NTLM Hash Disclosure Spoofing Vulnerability"
type: vulnerability-record
section: "Security Digest"
date_published: 2024-11-12
date_modified: 2025-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2024-43451"
kev: true
cvss: 6.5
epss: 0.84266
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2024-43451: Microsoft Windows NTLMv2 Hash Disclosure Spoofing Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Microsoft Windows. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2024-11-12, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2024-12-03 ; treat that as the outer limit, not the target.
- EPSS 84.3% , percentile 99.7: FIRST’s model estimates a 84.3% chance of exploitation activity in the next 30 days, higher than 99.7% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.

## What it is

NTLM Hash Disclosure Spoofing Vulnerability

## Affected products (CVE record)

- Microsoft Windows Server 2025: 10.0.26100.0 < 10.0.26100.2314
- Microsoft Windows Server 2025 (Server Core installation): 10.0.26100.0 < 10.0.26100.2314
- Microsoft Windows 10 Version 1809: 10.0.17763.0 < 10.0.17763.6532
- Microsoft Windows Server 2019: 10.0.17763.0 < 10.0.17763.6532
- Microsoft Windows Server 2019 (Server Core installation): 10.0.17763.0 < 10.0.17763.6532
- Microsoft Windows Server 2022: 10.0.20348.0 < 10.0.20348.2849
- Microsoft Windows 10 Version 21H2: 10.0.19043.0 < 10.0.19044.5131
- Microsoft Windows 11 version 22H2: 10.0.22621.0 < 10.0.22621.4460
- Microsoft Windows 10 Version 22H2: 10.0.19045.0 < 10.0.19045.5131
- Microsoft Windows 11 version 22H3: 10.0.22631.0 < 10.0.22631.4460

## Severity

- microsoft CVSS 3.1: 6.5 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:F/RL:O/RC:C`

## Exploitation

- CISA KEV: added 2024-11-12; federal due date 2024-12-03. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 84.27% probability of exploitation activity in the next 30 days; percentile 99.7.

## Sources

- [NTLM Hash Disclosure Spoofing Vulnerability](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-43451)
- [CVE.org record CVE-2024-43451](https://www.cve.org/CVERecord?id=CVE-2024-43451)
- [NVD entry CVE-2024-43451](https://nvd.nist.gov/vuln/detail/CVE-2024-43451)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-43451)

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Source page: https://erroneo.us/security/cve/CVE-2024-43451/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt