CVE-2025-58855: AP HoneyPot WordPress Plugin XSS Flaw

CVE-2025-58855 Overview

CVE-2025-58855 is an Improper Neutralization of Formula Elements in a CSV File vulnerability [CWE-1236] affecting the Denis V (Artprima) AP HoneyPot WordPress plugin (ap-honeypot). The flaw affects all versions up to and including 1.4. Attackers can inject spreadsheet formula payloads into data captured by the plugin. When an administrator exports the data to CSV and opens it in a spreadsheet application, the formulas execute. The advisory associates the issue with Reflected Cross-Site Scripting (XSS) behavior, requiring user interaction to trigger.

Critical Impact
Successful exploitation can lead to formula execution in spreadsheet applications, enabling data exfiltration, command execution through legacy DDE channels, or reflected script execution against the WordPress administrator session.

Affected Products

AP HoneyPot WordPress Plugin (ap-honeypot) versions through 1.4
WordPress sites using the Artprima HoneyPot extension for spam protection
Administrators exporting captured honeypot data to CSV format

Discovery Timeline

2025-09-05 - CVE-2025-58855 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-58855

Vulnerability Analysis

The vulnerability stems from the plugin failing to neutralize formula-triggering characters in user-supplied input before writing it into CSV exports. CSV Injection, also tracked as Formula Injection, occurs when fields beginning with =, +, -, @, or tab/carriage return characters are interpreted as formulas by spreadsheet software such as Microsoft Excel, LibreOffice Calc, or Google Sheets.

An unauthenticated attacker submits crafted input through a public-facing form protected by the honeypot. The plugin stores this input verbatim. When a site administrator later exports honeypot logs, the malicious payload lands in the CSV file. Opening the file executes the embedded formula in the administrator's context.

The advisory also classifies the issue as Reflected XSS, indicating that the unsanitized input is reflected back into administrative views, where script payloads can execute in the browser.

Root Cause

The plugin does not sanitize or escape leading formula characters in fields written to CSV output. The standard mitigation is to prefix suspect cells with a single quote or tab character so spreadsheet applications treat the content as literal text. The plugin omits this defense and additionally fails to encode the same data when reflected in the WordPress admin UI.

Attack Vector

Exploitation requires network access to a form protected by AP HoneyPot and user interaction from an administrator. The attacker submits a payload such as =cmd|'/C calc'!A1 or a =HYPERLINK() formula pointing to an attacker-controlled host. When the administrator opens the exported CSV, the formula executes and may exfiltrate adjacent cell content, trigger Dynamic Data Exchange (DDE) commands in unpatched Excel configurations, or render reflected XSS payloads in the admin dashboard.

Detection Methods for CVE-2025-58855

Indicators of Compromise

CSV exports from the AP HoneyPot plugin containing fields beginning with =, +, -, or @
Outbound network connections from spreadsheet processes (excel.exe, soffice.bin) to unknown hosts after opening plugin exports
Suspicious HTTP requests to honeypot-protected forms containing formula-style payloads or <script> tags
WordPress admin sessions exhibiting unexpected JavaScript execution when viewing honeypot logs

Detection Strategies

Inspect stored honeypot records for entries containing leading spreadsheet metacharacters before export
Monitor endpoints for spreadsheet applications spawning child processes such as cmd.exe or powershell.exe
Review web access logs for POST requests to honeypot-protected endpoints containing =, =HYPERLINK, =WEBSERVICE, or DDE syntax
Apply behavioral analytics to identify office applications initiating outbound network requests immediately after file open events

Monitoring Recommendations

Enable WordPress audit logging for plugin export actions performed by administrators
Forward endpoint telemetry to a SIEM and alert on Office or Calc applications launching scripting interpreters
Track plugin version inventory across managed WordPress sites to identify installations at or below 1.4

How to Mitigate CVE-2025-58855

Immediate Actions Required

Upgrade the AP HoneyPot plugin to a version released after 1.4 once the vendor publishes a fix
Avoid opening untrusted CSV exports directly in spreadsheet applications until the plugin is patched
Audit existing honeypot records and purge entries containing formula metacharacters before exporting
Restrict export functionality to a minimum number of trusted administrators

Patch Information

At the time of publication, the Patchstack WordPress Plugin Advisory tracks the issue against versions through 1.4. Administrators should monitor the plugin's WordPress.org page for an updated release and apply it across all sites.

Workarounds

Disable or remove the AP HoneyPot plugin until a patched release is available
Configure spreadsheet applications to disable automatic formula evaluation and DDE execution
Open exported CSV files in a plain text editor to inspect contents before loading into Excel or Calc
Implement a web application firewall rule to block form submissions containing leading =, +, -, or @ characters in honeypot-protected fields

bash

# Example WAF rule to block formula injection payloads in form submissions
ModSecurity rule:
SecRule ARGS "@rx ^[=+\-@]" \
    "id:1058855,phase:2,deny,status:403,\
    msg:'CSV Formula Injection attempt blocked (CVE-2025-58855)'"