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Threats / Trend Micro / CVE-2020-8599
CVE-2020-8599 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Trend Micro Apex One and OfficeScan vulnerability

Trend Micro Apex One and OfficeScan contain a vulnerable EXE file allowing remote attackers to write data to arbitrary paths and bypass root login authentication.

Verdict

Today item — known-exploited.

A remote code execution and authentication bypass vulnerability in Trend Micro endpoint protection products enables attackers to compromise server integrity without credentials. Active exploitation in the wild increases operational risk.

CISA KEV Yes · 2021-11-033EPSS 0.11576 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
cisa.gov ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.11576 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
FIRST EPSS ↗High
Severity / affected
Affected: Trend Micro, Apex One and OfficeScan. 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 identify the vulnerable EXE file exposed on the Trend Micro server.
Business
Endpoint protection infrastructure becomes a direct attack surface rather than a defensive layer.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I send a crafted request to write malicious data to an arbitrary path on the server.
Business
System files or configurations are corrupted or replaced, degrading or disabling security controls.
3

Lateral reach — past segmentation narrative 3

Attacker
I bypass root authentication mechanisms to gain administrative access.
Business
Attackers obtain full control of the security management console and all protected endpoints.
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)
  • 1 reported-exploitation source(s)
  • Catalogued by trendmicro (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 trendmicroCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.