External risk intelligence

Participants Database Unauthenticated Arbitrary File Deletion

CVE advisorySeverity: CRITICAL (CVSS 10.0)

CVE-2026-59555

The vulnerability affects a WordPress plugin, which functions as a web application component. These are commonly deployed as internet-facing services, making the application's features and endpoints, including those managed by plugins, typically accessible to public network traffic.

Path Traversal

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This critical vulnerability allows unauthenticated attackers to delete arbitrary files within the Participants Database application, potentially impacting data integrity and system availability. While the specific business impact depends on how this application is used within your organization, its critical severity and network accessibility warrant careful review to confirm relevance and exposure.

Attackers can delete files without logging in.
Data loss or system disruption is possible.
Confirm if this software is used in your environment.

Attack Path

How an attacker could exploit the issue

An attacker can initiate an attack remotely without needing any special privileges or user interaction. By sending a specially crafted request to the vulnerable plugin, they can target the participant database. This can lead to the deletion of arbitrary files on the server, potentially causing significant disruption and data loss.

No authentication required.
Triggered via network request.
Risk of arbitrary file deletion.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an unauthenticated attacker to delete arbitrary files from the server when the Participants Database plugin is installed and active. This could impact system stability and data integrity, potentially affecting the availability of the website and its associated data.

Arbitrary files on the server.
Unauthenticated network access to plugin.
System instability and data loss.

Operational Fix

Recommended remediation, mitigation, and detection steps

The unauthenticated arbitrary file deletion vulnerability in Participants Database affects external-facing web applications, likely managed by application owners or web administrators. The first critical step is to identify all instances of the affected plugin, confirm their network exposure and business criticality, and then assign an owner for remediation planning.

Application owners should investigate and remediate.
Verify plugin reachability and business impact.
Plan and coordinate necessary updates.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

Free EASM Trial See How Signal Works

Frequently asked questions

What is the Participants Database plugin?

Participants Database is a WordPress plugin used to manage and display lists of people, such as member directories or registration forms. It creates a database structure within a website, allowing site owners to collect, store, and present participant information directly through their WordPress dashboard and public-facing web pages.

What does CVE-2026-59555 mean for my site?

This vulnerability is classified as Improper Limitation of a Pathname to a Restricted Directory, or CWE-22. It means the software does not properly validate file paths during certain operations. Because of this flaw, an unauthorized person can send a specific command that tricks the plugin into deleting files on your server that it should not have access to, potentially damaging your website's core functionality or data.

How can an attacker trigger this vulnerability?

An attacker triggers this by sending a specially crafted request over the network to the affected WordPress site. Because the plugin does not require any login or user session to process these requests, the attacker can initiate the file deletion command remotely. This vulnerability is not triggered by standard site navigation or legitimate user actions, but rather through malicious, targeted inputs designed to manipulate the plugin's file handling.

Is my installation at risk?

Halo Surface Signal identifies this as a likely risk because Participants Database operates as an internet-facing WordPress component. If your site is accessible to the public, the plugin's features are reachable by external network traffic, increasing the likelihood that an attacker could attempt this exploit. Installations that are kept strictly internal or are not connected to public networks may have a reduced risk profile.

What should I do if I use this plugin?

Your first step is to perform an inventory of your WordPress installations to confirm if version 2.7.8.3 or older is currently active. Once identified, document the business purpose of those sites to prioritize your response. Ensure you are prepared to apply official updates as soon as they become available from the vendor and consider disabling the plugin temporarily if you cannot immediately verify its security status.

References

patchstack.com/database/wordpress/plugin/participants-database/vulne…

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.