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Threats / Microsoft / CVE-2024-21412
CVE-2024-21412 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Windows vulnerability

Microsoft Windows Internet Shortcut Files vulnerability allows security feature bypass. Actively exploited in ransomware campaigns.

Verdict

Today item, not a backlog item.

A security feature bypass in Windows Internet Shortcut Files enables attackers to circumvent protections and establish initial access. Active exploitation in ransomware operations demonstrates immediate threat to enterprise environments.

CISA KEV Yes · 2024-02-133Ransomware use Flagged3EPSS 0.95443 (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
31 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 2024-02-13), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.95443 — 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-693 Protection Mechanism Failure.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
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
Craft a malicious Internet Shortcut file that bypasses Windows security mechanisms to execute arbitrary code.
Business
Endpoint security controls fail to prevent malware execution, enabling unauthorized code execution on user systems.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
Distribute the weaponized shortcut file via email or file sharing to gain initial system access.
Business
User systems become compromised, providing attackers with foothold for lateral movement and data exfiltration.
3

Lateral reach — past segmentation narrative 3

Attacker
Deploy ransomware payload post-compromise to encrypt critical business data and demand payment.
Business
Operations halt due to encrypted systems; financial loss from ransom demands, recovery costs, and business interruption.
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)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Public PoC available (VulnCheck)
  • 31 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.