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Threats / Microsoft / CVE-2020-0674
CVE-2020-0674 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Internet Explorer vulnerability

Microsoft Internet Explorer contains a memory corruption vulnerability in the Scripting Engine that could allow remote code execution in the current user's context.

Verdict

Today item — known-exploited.

A use-after-free flaw in Internet Explorer's Scripting Engine enables remote code execution. The high EPSS score and active exploitation in the wild indicate immediate risk to unpatched systems.

CISA KEV Yes · 2021-11-033EPSS 0.86863 (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
10 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 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.86863 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Internet Explorer. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-416 Use After Free — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-416 · Use After FreeMemory safety
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 malicious webpage containing specially crafted JavaScript that triggers improper object handling in the Scripting Engine.
Business
Users visiting untrusted or compromised websites face arbitrary code execution with their privileges, risking credential theft and system compromise.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I host the exploit on a website or distribute it via phishing to increase victim reach.
Business
Attack surface expands across web browsing, email, and social engineering vectors, affecting both targeted and opportunistic victims.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code within the user's session to establish persistence or exfiltrate sensitive data.
Business
Confidentiality and integrity of user data are compromised; attackers gain foothold for lateral movement within 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)
  • 10 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.