SARA / Free Tools / KEV / CVE-2021-40539

CVE-2021-40539: Used in ransomware campaigns — CISA KEV

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

CISA KEV — Actively Exploited

Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resulta

Vendor / Product
— / —
Added to KEV
—
BOD 22-01 due
—
Ransomware use
Known
CVSS / EPSS
9.8 — · EPSS —

01What CISA says about this vulnerability

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

02Required action — verbatim from CISA

- CISA KEV: Apply updates per vendor instructions.

03Notes & references

No additional references available in the KB record.

04SARA's analyst layer — why this matters

This vulnerability is currently on the CISA KEV list, which CISA only adds CVEs to when there is reliable evidence of active exploitation in the wild. For federal civilian agencies, BOD 22-01 requires remediation by the due date above. For everyone else, KEV is the strongest "patch immediately" signal you can get from public threat intel.

05Affected products (summary)

No structured affected-product list available — see references below for vendor advisories.

06Detection

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection:

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