How severe is CVE-2021-36742?

CVE-2021-36742 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-36742 being actively exploited?

Yes. CVE-2021-36742 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-36742?

CVE-2021-36742 primarily affects Trendmicro Officescan. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36742?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-36742 have an EU (EUVD) identifier?

Yes. CVE-2021-36742 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-23332. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2021-36742 published?

CVE-2021-36742 was published on 2021-07-29 and last updated on 2026-06-17.

CVE-2021-36742

CVE-2021-36742 is a high-severity vulnerability in Trendmicro Officescan with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2021-23332
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-20
Affected product: Trendmicro Officescan
Published: 2021-07-29
Last modified: 2026-06-17

Description

A improper input validation vulnerability in Trend Micro Apex One, Apex One as a Service, OfficeScan XG and Worry-Free Business Security 10.0 SP1 allows a local attacker to escalate privileges on affected installations. Please note: an attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.

Frequently asked questions

What is CVE-2021-36742?: A improper input validation vulnerability in Trend Micro Apex One, Apex One as a Service, OfficeScan XG and Worry-Free Business Security 10.0 SP1 allows a local attacker to escalate privileges on affected installations. Please note: an attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
How severe is CVE-2021-36742?: CVE-2021-36742 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-36742 being actively exploited?: Yes. CVE-2021-36742 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-36742?: CVE-2021-36742 primarily affects Trendmicro Officescan. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36742?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-36742 have an EU (EUVD) identifier?: Yes. CVE-2021-36742 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-23332. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2021-36742 published?: CVE-2021-36742 was published on 2021-07-29 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:trendmicro:officescan:xg:sp1:*:*:*:*:*:*
cpe:2.3:a:trendmicro:officescan_business_security:10.0:sp1:*:*:*:*:*:*
cpe:2.3:a:trendmicro:apex_one:2019:*:*:*:*:*:*:*
cpe:2.3:a:trendmicro:worry-free_business_security:10.0:sp1:*:*:*:*:*:*

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