CVE-2021-40539

CVE Enrichment

CVSS: 9.8 CRITICAL
EPSS: 98.96%
EPSS Percentile: 99.93%
CISA KEV: YES — Known Exploited Vulnerability

Description

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

Technical Details

CVSS Version: 3.1
CNA / NVD Source: [email protected]
Published: 08-Sep-2021 00:15
Last Modified: 17-Jun-2026 11:07
EPSS Date: 2026-10-18
CWE: CWE-706

CVSS Vector


            CVSS:3.1                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:H /
                            I:H /
                            A:H

CISA KEV Details

Date Added: 2021-11-03
Remediation Due: 2021-11-17
Known Ransomware Campaign Use: Known
Required Action: Apply updates per vendor instructions.
Notes: https://nvd.nist.gov/vuln/detail/CVE-2021-40539

Affected Products / Versions

zohocorp / manageengine_adselfservice_plus
Version / affected range: * · before (exclusive) 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:*:*:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:-:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6100:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6101:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6102:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6103:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6104:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6105:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6106:*:*:*:*:*:*
zohocorp / manageengine_adselfservice_plus
Version / affected range: 6.1
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6113:*:*:*:*:*:*

References

Last enrichment sync: 25-Oct-2026 17:28
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (1)

Zoho ManageEngine ADSelfService Plus (CVE-2021-40539) Volt Typhoon’s Reported Intrusions Use Compromised Network Appliances for C2 Relays

Threat Actors (1)

MITRE ATT&CK (3)

Vendors (8)

Products (3)

Tools (1)

Industries (2)

Countries (1)

Note: Related entities, including threat actors, malware, CVEs, MITRE ATT&CK techniques, vendors, products, tools, countries, and industries, are shown when they appear in the same reporting. Their presence does not necessarily mean they were targeted, compromised, vulnerable, responsible for the activity, or directly involved in the incident.