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Threats / Microsoft / CVE-2024-43451
CVE-2024-43451 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Windows vulnerability

Microsoft Windows NTLMv2 hash spoofing vulnerability allows attackers to disclose user authentication hashes via file operations, enabling user impersonation.

Verdict

Today item — known-exploited.

An attacker can trigger NTLMv2 hash disclosure through a file open operation, capture the hash, and use it to impersonate the affected user within the network, bypassing authentication controls.

CISA KEV Yes · 2024-11-123EPSS 0.81817 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
17 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-11-12).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.81817 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-73 CWE-73 — weakness family: Path traversal / file.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-73 · CWE-73Path traversal / file
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I craft a file operation that triggers the target system to transmit its NTLMv2 hash to my controlled location.
Business
User authentication credentials are exposed to network-based capture and offline cracking attempts.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I intercept or receive the NTLMv2 hash and use it to authenticate as the legitimate user without knowing their password.
Business
Lateral movement and privilege escalation become possible as the attacker operates with legitimate user credentials.
3

Lateral reach — past segmentation narrative 3

Attacker
I access resources and systems that the impersonated user can reach, exfiltrating data or establishing persistence.
Business
Confidential data is compromised and attackers gain sustained access to critical systems and networks.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • Public PoC available (VulnCheck)
  • 17 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by microsoft (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by microsoftCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.