CVE-2019-25337Public exploitNetwork attack vectorHinoki check available

Authenticated username enumeration via wildcard share search

Published Feb 12, 2026 · Updated Feb 12, 2026

Username enumeration in ownCloud Classic 8.1.8 allows remote authenticated users to discover user accounts through the sharing API. The core/ajax/share.php handler accepts a wildcard search value and returns JSON containing usernames instead of restricting the recipient lookup. A valid low-privilege account and request token are required; the response discloses account names but does not alter accounts or files.

CVSS severity5.3
Medium
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Username enumeration in ownCloud Classic 8.1.8 allows remote authenticated users to discover user accounts through the sharing API. The core/ajax/share.php handler accepts a wildcard search value and returns JSON containing usernames instead of restricting the recipient lookup. A valid low-privilege account and request token are required; the response discloses account names but does not alter accounts or files.

The record

CVE
CVE-2019-25337
Published
Feb 12, 2026
Updated
Feb 12, 2026
Vendor
ownCloud
Product
ownCloud Classic
Classifications
CWE-203, T1087
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 12, 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=8.1.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ownCloud · ownCloud Classicversion=8.1.8

Published CVSS scores

9.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
5.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-203Observable Discrepancy
T1087Account Discovery

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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