# CVE-2021-40539

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

- Page: https://www.vulneraibility.com/cve/CVE-2021-40539
- CVSS: 9.8
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2021-11-17; known ransomware use
- EPSS: 98.96% (percentile 99.9)
- Public exploit code: 1 Metasploit module · 5 GitHub proofs of concept · 1 Nuclei template (first 2021-09-17)
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2025-02-03)
- Weakness: CWE-706
- Published: 2021-09-07

## Affected

- zohocorp:manageengine_adselfservice_plus

## References

- [other] https://www.manageengine.com
- [other] https://www.manageengine.com/products/self-service-password/kb/how-to-fix-authentication-bypass-vulnerability-in-REST-API.html
- [other] http://packetstormsecurity.com/files/165085/ManageEngine-ADSelfService-Plus-Authentication-Bypass-Code-Execution.html
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40539

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.