How severe is CVE-2021-37417?

CVE-2021-37417 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-37417 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37417?

CVE-2021-37417 primarily affects Zohocorp Manageengine Adselfservice Plus. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-37417?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-37417 published?

CVE-2021-37417 was published on 2021-08-30 and last updated on 2026-06-17.

CVE-2021-37417

CVE-2021-37417 is a critical-severity vulnerability in Zohocorp Manageengine Adselfservice Plus with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 5.0
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Zohocorp Manageengine Adselfservice Plus
Published: 2021-08-30
Last modified: 2026-06-17

Description

Zoho ManageEngine ADSelfService Plus version 6103 and prior allows CAPTCHA bypass due to improper parameter validation.

Frequently asked questions

What is CVE-2021-37417?: Zoho ManageEngine ADSelfService Plus version 6103 and prior allows CAPTCHA bypass due to improper parameter validation.
How severe is CVE-2021-37417?: CVE-2021-37417 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-37417 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37417?: CVE-2021-37417 primarily affects Zohocorp Manageengine Adselfservice Plus. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-37417?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-37417 published?: CVE-2021-37417 was published on 2021-08-30 and last updated on 2026-06-17.

References

https://blog.stmcyber.com/vulns/cve-2021-37417/

Affected products (6)

cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:*:*:*:*:*:*:*:*
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:-:*:*:*:*:*:*
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6100:*:*:*:*:*:*
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6101:*:*:*:*:*:*
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6102:*:*:*:*:*:*
cpe:2.3:a:zohocorp:manageengine_adselfservice_plus:6.1:6103:*:*:*:*:*:*

More vulnerabilities in Zohocorp Manageengine Adselfservice Plus

CVE-2019-3905 — Critical (CVSS 10.0): Zoho ManageEngine ADSelfService Plus 5.x before build 5703 has SSRF.
CVE-2023-35854 — Critical (CVSS 9.8): Zoho ManageEngine ADSelfService Plus through 6113 has an authentication bypass that can be exploited to steal the…
CVE-2022-47966 — Critical (CVSS 9.8): Multiple Zoho ManageEngine on-premise products, such as ServiceDesk Plus through 14003, allow remote code execution due…
CVE-2021-37422 — Critical (CVSS 9.8): Zoho ManageEngine ADSelfService Plus 6111 and prior is vulnerable to SQL Injection while linking the databases.
CVE-2021-37423 — Critical (CVSS 9.8): Zoho ManageEngine ADSelfService Plus 6111 and prior is vulnerable to linked applications takeover.
CVE-2021-40539 — Critical (CVSS 9.8): Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with…

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Other CWE-287 (Improper Authentication) vulnerabilities

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CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

Browse all CWE-287 (Improper Authentication) vulnerabilities →