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CVE-2021-40539: Zoho ManageEngine ADSelfService Plus Authentication Bypass Vulnerability
Zoho ManageEngine · in CISA KEV since 2021-11-03
2021-11-03added to KEV
2021-11-17federal remediation due date
98.96%EPSS exploit probability (30 days) 99.9th percentile
9.8 CRITICALCVSS 3.1
Knownknown ransomware use
57days from NVD publication to KEV
What it is
Zoho ManageEngine ADSelfService Plus contains an authentication bypass vulnerability affecting the REST API URLs which allow for remote code execution.
Required action (CISA)
Apply updates per vendor instructions.
| CWE | CWE-55 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-09-07 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-40539.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.