CVE-2021-4339Public exploitNetwork attack vector

User email disclosure via unauthenticated REST search

Published Jun 7, 2023 · Updated Apr 8, 2026

Missing authorization in StylemixThemes uListing 1.6.6 and earlier allows remote attackers to retrieve WordPress users and email addresses. The /1/api/ulisting-user/search route invokes StmUser::search without checking list_users, and the method returns IDs, names, and email addresses from WP_User_Query results. No authentication or user interaction is required; disclosure is limited to user-directory data returned by the search endpoint.

CVSS severity7.5
High
EPSS probability0.95%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in StylemixThemes uListing 1.6.6 and earlier allows remote attackers to retrieve WordPress users and email addresses. The /1/api/ulisting-user/search route invokes StmUser::search without checking list_users, and the method returns IDs, names, and email addresses from WP_User_Query results. No authentication or user interaction is required; disclosure is limited to user-directory data returned by the search endpoint.

The record

CVE
CVE-2021-4339
Published
Jun 7, 2023
Updated
Apr 8, 2026
Vendor
StylemixThemes
Product
uListing
Classifications
CWE-862, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 7, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <1.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

StylemixThemes · uListingversion=0 <1.7

Published CVSS scores

7.5WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.3NIST NVDCVSS: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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1190Exploit Public-Facing Application

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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