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Threats / Microsoft / CVE-2016-3351
CVE-2016-3351 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Internet Explorer and Edge vulnerability

Information disclosure vulnerability in Internet Explorer and Edge memory handling allows attackers to detect specific files on a user's computer.

Verdict

Today item, not a backlog item.

An information disclosure flaw in how Internet Explorer and Edge process objects in memory enables file detection attacks. Exploitation has been observed in the wild and linked to ransomware campaigns, indicating active adversary interest.

CISA KEV Yes · 2022-05-243Ransomware use Flagged3EPSS 0.26286 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
6 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), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.26286 — 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 and Edge. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-200 Information Exposure — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-200 · Information ExposureAuthorization / access control
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 that triggers improper memory object handling in the target's browser.
Business
User visits attacker-controlled or compromised website without additional security warnings.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I observe memory disclosure patterns to infer the presence or absence of specific files on the victim's system.
Business
Attacker gains reconnaissance data about system configuration and installed software.
3

Lateral reach — past segmentation narrative 3

Attacker
I use file detection results to tailor follow-up attacks, such as deploying ransomware variants targeting detected applications.
Business
Ransomware deployment becomes more precise and effective, increasing encryption scope and ransom leverage.
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)
  • 6 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.