CVE-2026-39527

WordPress WpStream plugin < 4.11.2 - Arbitrary File Upload vulnerability

Published Jun 15, 2026 CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed

Description

Subscriber Arbitrary File Upload in WpStream < 4.11.2 versions.

Analysis

Technical impact

The WpStream plugin accepts file uploads without proper type validation, as identified by CWE-434. The description notes that an attacker could upload any file through the plugin’s web interface. However, the CVE does not state that the uploaded file can be executed, so the impact is limited to arbitrary file upload.

Affected Systems

Installed instances of the WordPress WpStream plugin version 4.11.1 and earlier are vulnerable. Sites that allow regular subscribers or non‑administrator users to upload media via the plugin are especially exposed.

Risk and Exploitability

The CVSS score of 5.4 indicates moderate severity for a user interacting via the web, and the EPSS score of less than 1 % suggests the likelihood of exploitation is very low. The vulnerability is not listed in the CISA KEV catalog. A remote attacker who can reach the site is able to upload a file through the plugin’s front‑end. The description does not confirm that uploaded scripts can be executed, but arbitrary file upload could potentially compromise the site.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

sc Internet Vivoo

WpStream

unaffected

Version	Status	Constraints
`n/a`	affected	< 4.11.2

No data.

Vendor Product Versions

Sc Internet Vivoo

Wpstream

Version	Status	Scheme	Platform
`[0,4.11.2)`	affected	semver	—
`[4.11.2,*]`	unaffected	semver	—

Wordpress

Version	Status	Scheme	Platform
`—`	unaffected	—	—

Remediation

Vendor Solution

Update the WordPress WpStream Plugin to the latest available version (at least 4.11.2).

OpenCVE Recommended Actions

Upgrade the WordPress WpStream plugin to version 4.11.2 or newer.
Restrict upload permissions for non‑administrator users so that only trusted roles can submit files through the plugin.
Configure the server or the plugin to allow only a whitelist of safe file types and enforce strict size limits to block unintended uploads.
Consider deploying a web application firewall rule that blocks suspicious upload attempts or patterns indicative of malicious content.

Generated by OpenCVE AI on June 18, 2026 at 07:14 UTC.

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact Low

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.291% probability within 30 days)

Exploitation none

Automatable no

Technical Impact partial

References

Link	Providers
https://patchstack.com/database/wordpress/plugin/wpstream/vulnerability/wordpress-wpstream-plugin-4-11-2-arbitrary-file-upload-vulnerability?_s_id=cve

History

Jun 23, 2026 9:30 PM First appearance in the feed. Affected vendors updated View changes

Type	Values Removed	Values Added
First Time appeared		Sc Internet Vivoo Sc Internet Vivoo wpstream Wordpress Wordpress wordpress
Vendors & Products		Sc Internet Vivoo Sc Internet Vivoo wpstream Wordpress Wordpress wordpress

Jun 15, 2026 11:30 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Jun 15, 2026 8:30 PM Description updated. Title updated. Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		Subscriber Arbitrary File Upload in WpStream < 4.11.2 versions.
Title		WordPress WpStream plugin < 4.11.2 - Arbitrary File Upload vulnerability
Weaknesses		CWE-434
References		https://patchstack.com/database/wordpress/plugin/wpstream/vulnerability/wordpress-wpstream-plugin-4-11-2-arbitrary-file-upload-vulnerability?_s_id=cve
Metrics		cvssV3_1 `{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L'}`