What is the CVSS score of CVE-2019-25337?

CVE-2019-25337 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

Is there a public PoC exploit available for CVE-2019-25337?

Yes, a public proof-of-concept exploit is available for CVE-2019-25337. Prioritise patching immediately. EPSS: 0.1%.

How to fix or mitigate CVE-2019-25337?

Within 24 hours: Inventory all OwnCloud 8.1.8 deployments and disable or restrict public access to share.php endpoint via WAF or network controls. Within 7 days: Implement rate limiting and access logging on share.php to detect exploitation attempts; notify users of potential account enumeration. Within 30 days: Migrate to a supported OwnCloud version or evaluate alternative file-sharing solutions with active security support.

PHP CVE-2019-25337

CRITICAL

Observable Discrepancy (CWE-203)

2026-02-12 disclosure@vulncheck.com

PHP

9.8

CVSS 3.1 · NVD

View

Vulnerability Assessment

Weakness	CWE CWE-203 OWASP Top 10:2025 A06:2021 - Vulnerable and Outdated Components ASVS 5.0 V6 - Authentication Timing-safe comparisons
Impact	CVSS 9.8. Enables targeted attacks on known accounts.
Exploit ScenarioDerived	Attacker enumerates valid usernames through response timing/content differences.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.

No patch listed yet 0.1% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 12, 2026

Username enumeration in OwnCloud 8.1.8 via share.php endpoint. PoC available.

Earlier versions of this analysis (1)

v1 Mar 12, 2026 - 22:02 CVSS 9.8

Username enumeration in OwnCloud.

RemediationAI

Update OwnCloud.

Affected ProductsAI

OwnCloud 8.1.8

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

CWE-203 observable discrepancy in share.php responses.

Know when PHP gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

PoC Detected

Feb 13, 2026 - 14:23 vuln.today

Public exploit code

CVE Published

Feb 12, 2026 - 23:16 nvd

CRITICAL 9.8

DescriptionCVE.org

OwnCloud 8.1.8 contains a username enumeration vulnerability that allows remote attackers to discover user accounts by manipulating the share.php endpoint. Attackers can send crafted GET requests to /index.php/core/ajax/share.php with a wildcard search parameter to retrieve comprehensive user information.

Executive ViewAI

Why It Matters

OwnCloud 8.1.8 instances are vulnerable to username enumeration attacks that allow unauthenticated attackers to systematically discover valid user accounts through the share.php endpoint. This exposure directly compromises user privacy and enables targeted credential attacks, phishing campaigns, and social engineering against identified personnel.

Business Impact: High

Compensating Controls

Implement WAF rules to block or rate-limit requests to share.php; restrict share.php endpoint access to authenticated users only via reverse proxy or firewall ACLs; disable public share functionality if not business-critical; enable comprehensive logging and SIEM monitoring of share.php requests for enumeration patterns; consider network segmentation to limit exposure of OwnCloud instance.

Threat Intelligence Overview

EPSS Score

0.1%

Top 68% exploitable

Exploit

POC

Public exploit code exists

Data Quality

4 sources

Confidence: Medium

NVD

CVE.org

EPSS

Exploit-DB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC Yes

EPSS 0.1%

Patch available No

Active threat No

Deciding rule

CRITICAL severity + public POC available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Out-of-Cycle

Exploitation· derived

Poc

System Exposure· derived

Open

Automatable· derived

Yes

Human Impact

High

Priority Score

Low Medium High Critical

KEV: 0

EPSS: 0

CVSS: +49

PoC: +20

Weaponized: 0

Threat intel: 0

Gov advisory: 0

More in PHP

View all

CVE-2019-11043 CRITICAL Emergency POC

9.8 Oct 28

In PHP versions 7.1.x below 7.1.33, 7.2.x below 7.2.24 and 7.3.x below 7.3.11 in certain configurations of FPM setup it

CVE-2012-1823 CRITICAL Act Now POC

9.8 May 11

sapi/cgi/cgi_main.c in PHP before 5.3.12 and 5.4.x before 5.4.2, when configured as a CGI script (aka php-cgi), does not

CVE-2016-1555 CRITICAL Act Now POC

9.8 Apr 21

(1) boardData102.php, (2) boardData103.php, (3) boardDataJP.php, (4) boardDataNA.php, and (5) boardDataWW.php in Netgear

CVE-2018-11138 CRITICAL Emergency POC

9.8 May 31

The '/common/download_agent_installer.php' script in the Quest KACE System Management Appliance 8.0.318 is accessible by

CVE-2024-11680 CRITICAL Act Now POC

9.8 Nov 26

ProjectSend versions prior to r1720 are affected by an improper authentication vulnerability. Rated critical severity (C

CVE-2025-49113 CRITICAL Act Now POC

9.9 Jun 02

Roundcube Webmail contains a critical PHP object deserialization vulnerability (CVE-2025-49113, CVSS 9.9) that allows au

CVE-2017-9841 CRITICAL Act Now POC

9.8 Jun 27

Util/PHP/eval-stdin.php in PHPUnit before 4.8.28 and 5.x before 5.6.3 allows remote attackers to execute arbitrary PHP c

CVE-2025-0108 HIGH Act Now POC

8.8 Feb 12

Palo Alto Networks PAN-OS management web interface contains an authentication bypass allowing unauthenticated attackers

CVE-2021-25298 HIGH Act Now POC

8.8 Feb 15

Nagios XI version xi-5.7.5 is affected by OS command injection. Rated high severity (CVSS 8.8), this vulnerability is re

CVE-2021-25296 HIGH Act Now POC

8.8 Feb 15

Nagios XI version xi-5.7.5 is affected by OS command injection. Rated high severity (CVSS 8.8), this vulnerability is re

CVE-2013-4983 CRITICAL Emergency POC

10.0 Sep 10

The get_referers function in /opt/ws/bin/sblistpack in Sophos Web Appliance before 3.7.9.1 and 3.8 before 3.8.1.1 allows

CVE-2023-6553 CRITICAL Act Now POC

9.8 Dec 15

The Backup Migration plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 1

Same weakness CWE-203 – Observable Discrepancy

View all

CVE-2017-5753 MEDIUM POC

5.6

CVE-2017-13099 HIGH POC

7.5

CVE-2017-1000385 MEDIUM POC

5.9

CVE-2017-6168 HIGH POC

7.4

CVE-2017-13098 HIGH POC

7.5

CVE-2017-17427 MEDIUM POC

5.9

CVE-2018-3639 MEDIUM POC

5.5

CVE-2024-25191 CRITICAL POC

9.8

References

Advisories & patches

REF https://ftp.icm.edu.pl/packages/owncloud/ REF https://owncloud.org/ REF https://www.vulncheck.com/advisories/owncloud-username-disclosure

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back