Threats / Microsoft / CVE-2018-8414
CVE-2018-8414
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-09-19
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 · 2022-03-254EPSS 0.73968 (verify live)5Exploit Public PoC6CVSS 8.8 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3
01
Is it exploitable?
— the evidence, ranked above the scoreExploit 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).
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
CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) · Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 1318 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution 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 board1
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’tEstablished (cited)
Coverage gaps — stated, not hidden
Disclosure & credit2
Catalogued by microsoftCNA
Credited with finding itMatt Nelson ( @enigma0x3 ) of SpecterOpsfinder
Found an error? Propose a correction.
A correction is a cited counter-claim — it must cite a source,
gets reviewed by a second human, and is never auto-applied. See the
correction convention and our identity
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