Threats / Trend Micro / CVE-2021-36742
CVE-2021-36742
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Trend Micro Apex One, One as a Service, and Worry-Free Busin vulnerability
Trend Micro Apex One, Apex One as a Service, and Worry-Free Business Security contain an improper input validation vulnerability enabling privilege escalation. The flaw has been exploited in the wild.
Verdict
Today item — known-exploited.
An unauthenticated or low-privileged attacker can exploit improper input validation in Trend Micro endpoint protection products to gain elevated system privileges, potentially compromising security controls across protected infrastructure.
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
2 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).
Probability (EPSS)
EPSS 0.01482 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Trend Micro, Apex One, Apex One as a Service, and Worry-Free Business Security. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution 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 board1
Front door — unauthenticated access narrative 1
Attacker
I craft malformed input to bypass validation checks in the affected Trend Micro product.
Business
Security controls designed to protect endpoints are circumvented through a validation defect.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I escalate my privileges on the compromised system by exploiting the validated input processing.
Business
An attacker gains administrative or system-level access to protected endpoints, enabling lateral movement and persistence.
3
Lateral reach — past segmentation narrative 3
Attacker
I disable or modify endpoint protection policies and logging to cover my tracks.
Business
Visibility into endpoint compromise is lost and security incident response is delayed or prevented.
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’tEstablished (cited)
Coverage gaps — stated, not hidden
Disclosure & credit2
Catalogued by trendmicroCNA
Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.