Is CVE-2021-40539 actively exploited?

CVE-2021-40539 has no public evidence of in-the-wild exploitation as of 2025-11-05.

What is the CVSS score for CVE-2021-40539?

CVE-2021-40539 has a CVSS score of 9.8 (CRITICAL severity). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

How do I patch CVE-2021-40539?

Patch guidance is available from zohocorp security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2021-40539.

Fix CVE-2021-40539 - CRITICAL

Q: Which products are affected by CVE-2021-40539?

10 products: zohocorp manageengine adselfservice plus, zohocorp manageengine adselfservice plus, zohocorp manageengine adselfservice plus, zohocorp manageengine adselfservice plus, zohocorp manageengine adselfservice plus, and 5 more.

Description

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

CVSS Metrics

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector: network
Complexity: low
Privileges: none
User Action: none
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: high
Weaknesses: CWE-706 CWE-706

Metadata

Primary Vendor: ZOHOCORP
Published: 9/7/2021
Last Modified: 11/5/2025
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

zohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_pluszohocorp : manageengine_adselfservice_plus

Remediation Guidance

Executive Summary

View on NIST NVD