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Threats / Microsoft / CVE-2017-0210
CVE-2017-0210 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Internet Explorer vulnerability

Internet Explorer privilege escalation via improper cross-domain policy enforcement allows attackers to access sensitive information.

Verdict

Today item — known-exploited.

A privilege escalation flaw in Internet Explorer's cross-domain policy enforcement enables unauthorized information disclosure. Active exploitation in the wild demonstrates practical threat; moderate EPSS score reflects real-world attack feasibility.

CISA KEV Yes · 2022-05-243EPSS 0.19522 (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 0.19522 — 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
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 exploits Internet Explorer's cross-domain policy bypass to escalate my privileges.
Business
User browsers become vectors for unauthorized data access, compromising confidentiality of sensitive information.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I leverage the privilege escalation to access restricted resources or information normally protected by domain boundaries.
Business
Attackers gain unauthorized visibility into user data across security domains, eroding trust in browser isolation mechanisms.
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)
  • 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.