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

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 12 Nov 2024, the same day the CVE record was published.

How likely is exploitation in the next 30 days?

84.3%

EPSS score, percentile 99.7 of all scored records

How severe?

6.5 Medium

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 3 Dec 2024. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Advisories and patches (1)

Which versions are affected?

Affected

• from 10.0.26100.0 to before 10.0.26100.2314
• from 10.0.26100.0 to before 10.0.26100.2314
• from 10.0.17763.0 to before 10.0.17763.6532
• from 10.0.17763.0 to before 10.0.17763.6532
• from 10.0.17763.0 to before 10.0.17763.6532
• from 10.0.20348.0 to before 10.0.20348.2849

and 14 more in the table below

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 3 December 2024.

Advisories and patches

• NTLM Hash Disclosure Spoofing Vulnerability (Vendor advisory)

Linked from CISA's catalog entry

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-43451
• https://nvd.nist.gov/vuln/detail/CVE-2024-43451

Affected products and versions

As listed in the CVE record.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Microsoft Windows contains an NTLMv2 hash spoofing vulnerability that could result in disclosing a user's NTLMv2 hash to an attacker via a file open operation. The attacker could then leverage this hash to impersonate that user.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2024-43451 to its Known Exploited Vulnerabilities (KEV) catalog on 12 Nov 2024.
• CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
• The due date CISA sets for the required action is 3 Dec 2024.
• The CVE record was published on 12 Nov 2024, the same day it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 6.5 (Medium), given by its CNA.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 84.3% (percentile 99.7), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact partial.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

NTLM Hash Disclosure Spoofing Vulnerability

NTLM Hash Disclosure Spoofing Vulnerability

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-73: External Control of File Name or Path

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

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