---
id: "CVE-2026-115806"
kind: "vulnerability"
aliases: ["CVE-2026-115806"]
title: "WordPress Prime Mover plugin: unauthenticated PHP object injection via comments"
severity: "critical"
cvss: 9.8
epss: 0.00819
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "prime-mover", "self-hosted", "wordpress", "wordpress-plugin"]
not_affected_if: ["plugin-not-installed", "version-above-2.2.1"]
published_at: "2026-10-24T05:17:04+00:00"
first_seen_at: "2026-10-24T05:46:56+00:00"
updated_at: "2026-10-25T12:38:49+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-115806", "first_seen_at": "2026-10-24T05:46:56+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-115806", "first_seen_at": "2026-10-25T12:38:49+00:00"}]
---

# WordPress Prime Mover plugin: unauthenticated PHP object injection via comments

Prime Mover, a WordPress backup and migration plugin, unserializes attacker-supplied data stored in comment content during export or restore, for all versions up to and including 2.2.1. An unauthenticated attacker can plant a crafted serialized object through the comment form, and the plugin's bundled Freemius library provides a gadget chain that can lead to code execution on the site.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed Prime Mover plugin version in the WordPress admin plugins list or the `prime-mover` plugin header; versions up to and including `2.2.1` are affected.
- unknown for whether comments containing base64-encoded serialized data already exist in `wp_comments`.

## Fix

- Update the Prime Mover plugin to a version later than `2.2.1`; the sources do not name the fixed version.
- Until updated, deactivate the Prime Mover plugin or restrict comment submission.

## Timeline

- 2026-10-24T05:46:56+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-115806
- 2026-10-25T12:38:49+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-115806

## From the sources

The Prime Mover – Backup and Migration plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 2.2.1 via deserialization of untrusted input in the migration search-and-replace routine (recursiveUnserializeReplace()). An unauthenticated attacker can store a crafted, base64-encoded serialized object in wp_comments.comment_content through the standard comment-submission endpoint (wp-comments-post.php). When an administrator subsequently performs a routine Prime Mover export or restore, the plugin base64-decodes that stored value and passes it to unserialize() with no allowed_classes restriction. A Property-Oriented Programming (POP) chain is present in the plugin's own bundled Freemius library (FS_Clone_Manager::__set → FS_Option_Manager::set_option → store() → update_option()), so no additional plugin or theme is required — the plugin ships the gadget itself.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_