{"id":"CVE-2021-36742","published":"2021-07-29T20:15:07Z","modified":"2026-06-17T03:59:05Z","title":"Trend Micro Multiple Products Improper Input Validation Vulnerability","vendor":"Trend Micro","product":"Apex One, Apex One as a Service, and Worry-Free Business Security","tier":"core","eol":null,"description":{"text":"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.","provenance":"source","from":"NVD"},"summary":{"text":"A improper input validation flaw in Trend Micro's Apex One, Apex One as a Service, OfficeScan XG and Worry-Free Business Security 10.0 SP1 products allows privilege escalation on affected installations. An attacker needs local access and must already be able to run low-privileged code on the target system, with no user interaction required.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T07:11:27Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.01482,"percentile":0.73893,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2021-11-03","dueDate":"2021-11-17","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://success.trendmicro.com/dcx/s/solution/000287819?language=en_US, https://success.trendmicro.com/dcx/s/solution/000287820?language=en_US; https://nvd.nist.gov/vuln/detail/CVE-2021-36742","provenance":"source"},"vulncheckKev":{"dateAdded":"2021-08-11","exploitedFirstSeen":"2021-08-11","ransomware":false,"evidence":[{"url":"https://therecord.media/hackers-tried-to-exploit-two-zero-days-in-trend-micros-apex-one-edr-platform","date":"2021-08-11"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2021-11-03"}],"evidenceTotal":2,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-20","name":"Improper Input Validation"}],"references":[{"url":"https://success.trendmicro.com/jp/solution/000287796","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/jp/solution/000287815","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/solution/000287819","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/solution/000287820","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/jp/solution/000287796","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/jp/solution/000287815","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/solution/000287819","tags":["Vendor Advisory"]},{"url":"https://success.trendmicro.com/solution/000287820","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-36742","tags":["US Government Resource"]}],"techniques":[{"id":"T1068","name":"Exploitation for Privilege Escalation","tactics":["privilege-escalation"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: local attacker exploits improper input validation for privilege escalation","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"allows a local attacker to escalate privileges on affected installations","start":146,"end":218}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2021-23332","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-23332","exploited":true,"exploitedSince":"2021-11-03","provenance":"source"},"exploits":[],"exploitSources":null,"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1068"],"provenance":"ai"}],"timeline":[{"date":"2021-07-29","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-36742","provenance":"source"},{"date":"2021-08-11","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://therecord.media/hackers-tried-to-exploit-two-zero-days-in-trend-micros-apex-one-edr-platform","provenance":"source"},{"date":"2021-11-03","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2021-11-03","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-23332","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":null,"daysToKev":97},"priority":{"score":58.2,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1905 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":14.78,"detail":"percentile 0.7389"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":0.0,"detail":"none found"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":5.46,"detail":"base score 7.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}