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Threats / Microsoft / CVE-2017-0149
CVE-2017-0149 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Internet Explorer vulnerability

Microsoft Internet Explorer memory corruption vulnerability allows remote code execution or denial-of-service through crafted websites.

Verdict

Today item — known-exploited.

Memory corruption flaw in Internet Explorer enables remote attackers to execute arbitrary code or crash the browser via malicious web content. Active exploitation observed in the wild.

CISA KEV Yes · 2022-05-243EPSS 0.29189 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
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 2022-05-24).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.29189 — 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-119 Memory Buffer Bounds Error — weakness family: Memory safety.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 malicious website containing specially formatted content that triggers a memory corruption bug in Internet Explorer's rendering engine.
Business
Users visiting the attacker's site or redirected content face immediate risk of system compromise or service disruption.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I host the exploit on a server or inject it into legitimate web traffic to reach target browsers without user awareness of the attack vector.
Business
Attack surface expands across all web-browsing activity; no additional user action required beyond normal browsing.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code with the privileges of the Internet Explorer process, establishing persistence or lateral movement within the victim's network.
Business
Compromised endpoints become entry points for data theft, malware deployment, or further network infiltration.
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)
  • 3 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • 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.