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Threats / Microsoft / CVE-2018-8414
CVE-2018-8414 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Windows vulnerability

Windows Shell remote code execution via improper file path validation. An attacker can execute arbitrary code by crafting malicious file paths that bypass validation checks.

Verdict

Today item — known-exploited.

A remote code execution vulnerability in Windows Shell stemming from insufficient input validation of file paths. Exploitation is feasible and has been observed in the wild, enabling attackers to achieve code execution with user interaction or system privileges depending on context.

CISA KEV Yes · 2022-03-253EPSS 0.73968 (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
3 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 2022-03-25).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.73968 — 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-20 Improper Input Validation.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
I craft a specially formatted file path designed to bypass Shell validation logic.
Business
Attackers gain a viable vector to compromise Windows systems at scale without requiring patched software.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the malicious path through email, file sharing, or network protocols that trigger Shell processing.
Business
Initial compromise occurs when users or automated systems process untrusted file references.
3

Lateral reach — past segmentation narrative 3

Attacker
I achieve remote code execution within the context of the Shell process or user session.
Business
Attackers establish persistent access, steal credentials, or pivot to critical systems within the organization.
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)
  • 3 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.