CVE-2021-33617Public exploitNetwork attack vector

Unauthenticated username enumeration via differential login responses

Published Jul 31, 2021 · Updated Aug 3, 2024

User enumeration in Zoho ManageEngine Password Manager Pro before build 11200 allows remote attackers to identify valid usernames via login endpoint. The login/AjaxResponse.jsp GetUserDomainName handler returns null only for invalid usernames, creating an observable response difference. No authentication is required, and the result exposes account names without granting access to accounts or stored passwords.

CVSS severity5.3
Medium
EPSS probability2.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

User enumeration in Zoho ManageEngine Password Manager Pro before build 11200 allows remote attackers to identify valid usernames via login endpoint. The login/AjaxResponse.jsp GetUserDomainName handler returns null only for invalid usernames, creating an observable response difference. No authentication is required, and the result exposes account names without granting access to accounts or stored passwords.

The record

CVE
CVE-2021-33617
Published
Jul 31, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-203, T1589
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
5.3NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-203Observable Discrepancy
T1589Gather Victim Identity Information

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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