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CVE DATABASE  /  CVE-2021-40539

CVE-2021-40539

Zoho ManageEngine ADSelfService Plus Authentication Bypass Vulnerability

CVSS 9.8 · CRITICAL ⚠ CISA KEV — ACTIVELY EXPLOITED RANSOMWARE
On the CISA KEV catalog

Confirmed exploited in the wild. Added 2021-11-03. Federal remediation due 2021-11-17.
Required action: Apply updates per vendor instructions.

Summary

Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code execution.

CVSS 3.1 breakdown

Base score9.8 (CRITICAL)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vectorNETWORK
Attack complexityLOW
Privileges requiredNONE
User interactionNONE
ScopeUNCHANGED
ConfidentialityHIGH
IntegrityHIGH
AvailabilityHIGH

Weakness type (CWE)

Affected products

Zohocorp manageengine adselfservice plus
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References

Data: NIST NVD + CISA KEV. NVD last modified 2025-11-05. Always verify against the vendor advisory before acting.

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