CVE-2021-40539
Zohocorp Manageengine Adselfservice Plus ≤ 6.1
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2021-40539 is a critical-severity Use of Incorrectly-Resolved Name or Reference (CWE-706) vulnerability in Zohocorp Manageengine Adselfservice Plus. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Path Interception (T1034); ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Zoho ManageEngine ADSelfService Plus versions 6113 and earlier contain a REST API authentication bypass vulnerability that leads directly to remote code execution. The flaw is tracked as CVE-2021-40539 and carries a CVSS 3.1 base score of 9.8, reflecting network-accessible exploitation without credentials or user interaction. The affected component is the product's REST API handling, classified under CWE-706.
Unauthenticated attackers can send specially crafted requests to the REST endpoints to circumvent authentication controls and obtain the ability to execute arbitrary code on the underlying server. Successful exploitation grants full control over the ManageEngine instance, including access to stored credentials and the ability to pivot within the managed Active Directory environment.
Vendor guidance published by ManageEngine directs administrators to apply the authentication bypass fix for the REST API; the company has released a knowledge-base article detailing the required remediation steps along with updated builds that address the issue. Public exploit code for the vulnerability has also been posted to Packet Storm.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-27714
Vulnerability Data
Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code execution.
- CWE(s)
- KEV Date Added
- 03 November 2021
Related Threats
MITRE ATT&CK Enterprise Techniques
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Affected Assets
Mitigating Controls
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure-development practices directly prevent incorrect name/reference resolution bugs during coding.
Enforced authorization boundaries limit damage from an incorrectly resolved reference.
Logical segmentation and access controls reduce the chance an out-of-sphere resolution succeeds.
Hardened configuration baselines can constrain allowable name-to-resource mappings.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect incorrect name or reference resolution through fuzzing and negative test cases.
Network segmentation and routing policies reduce the chance that a mis-resolved name leads to an unintended external resource.
Segregated networks limit the blast radius when a name or reference resolves outside the intended control sphere.
Secure SDLC practices include design reviews that can catch incorrect name or reference handling before deployment.
Application security requirements can mandate validation of all external references and names used at runtime.
Secure architecture principles discourage reliance on ambient or globally-resolvable names without explicit scoping.