CVE-2021-40539
Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code…
- 9.8CriticalCVSS base score
- 99.0%Exploitation in 30 daysEPSS · top 0.1% of all CVEs
- YesKnown exploitedin CISA's KEV since 3 Nov 2021
- 2Public exploitsMetasploit, Nuclei and Exploit-DB
Description
Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code execution.
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Zoho ManageEngine ADSelfService Plus Authentication Bypass Vulnerability.
- Added
- 3 Nov 2021
- Fix due (US federal)
- 17 Nov 2021
- Used by ransomware
- Known
Apply updates per vendor instructions.
ENISA's EU Vulnerability Database lists it as exploited, from CISA's KEV, since 3 Nov 2021.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module and a Nuclei template for it. CISA's SSVC rates its exploitation: it is being exploited.
Show the exploits2
Metasploit modules1 module
- ManageEngine ADSelfService Plus CVE-2021-40539 (Metasploit module) (opens in a new tab)
exploit/windows/http/manageengine_adselfservice_plus_cve_2021_40539Rank excellentdisclosed 7 Sept 2021
Nuclei templates1 template
- Zoho ManageEngine ADSelfService Plus v6113 - Unauthenticated Remote Command Execution (Nuclei template) (opens in a new tab)
http/cves/2021/CVE-2021-40539.yamlSeverity critical
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By mitre
- 1 day later
· 1 day later
Published
- 57 days later
· 57 days later
Added to CISA KEV
Known exploited, also by ransomware
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Analyzed | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 99.0% · top 0.1% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
n/a
- affected n/a
References
References4
- https://www.manageengine.com (opens in a new tab)x_refsource_MISCx_transferred
- https://www.manageengine.com/products/self-service-password/kb/how-to-fix-authentication-bypass-vulnerability-in-REST-API.html (opens in a new tab)x_refsource_MISCx_transferred
- http://packetstormsecurity.com/files/165085/ManageEngine-ADSelfService-Plus-Authentication-Bypass-Code-Execution.html (opens in a new tab)x_refsource_MISCx_transferred
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40539 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-27714 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-40539)Record last updated .