External risk intelligence

AI ANN PHP Object Injection Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-65581

The vulnerability affects a WordPress theme, which is a type of web application component. WordPress themes are commonly deployed as part of public-facing web applications, making the attack surface reachable via the internet in typical deployments.

Deserialization

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

A critical vulnerability exists in a widely used AI-powered WordPress theme that could allow unauthenticated attackers to inject malicious code. This flaw, if exploited, could lead to significant compromise of website data and functionality by enabling unauthorized access and control.

Unauthenticated code injection risk.
Impacts AI-powered website themes.
Confirm relevance and exposure.

Attack Path

How an attacker could exploit the issue

An unauthenticated attacker can exploit this vulnerability by sending a specially crafted request to a vulnerable installation. This could allow them to inject malicious PHP objects, potentially leading to the execution of arbitrary code on the server.

Unauthenticated network access required.
Triggered by sending a crafted request.
Allows arbitrary code execution.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability could allow an unauthenticated attacker to inject serialized PHP objects into a WordPress site using the AI ANN theme, potentially leading to the execution of arbitrary code.

Theme code and server-side processes.
Via unauthenticated injection of serialized objects.
Compromise of the website and its server.

Operational Fix

Recommended remediation, mitigation, and detection steps

The unauthenticated PHP Object Injection in AI ANN affects web applications, making platform or application owners responsible for identifying and mitigating this risk. The immediate first step is to confirm the presence and reachability of the affected AI ANN component within your environment, assess its business criticality, and then coordinate remediation with the accountable owner.

Application or platform owners should own the issue.
Verify AI ANN presence and external reachability.
Plan remediation based on risk and business impact.

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 AI ANN WordPress theme?

AI ANN is a specialized WordPress theme designed to integrate artificial intelligence features into websites. It serves as the visual and functional foundation for a site, managing how content is presented and how the server processes interactions. Because it is a theme, it runs directly on the web server, making it a central component of the site's architecture.

What does PHP Object Injection mean for CVE-2026-65581?

This vulnerability, classified as CWE-502, occurs when the software takes user-supplied input and improperly deserializes it. In plain terms, the theme trusts data it should not. By sending malicious serialized objects, an attacker can manipulate the application's logic, potentially tricking the server into executing unauthorized code or performing unintended actions.

How is the AI ANN vulnerability triggered?

An attacker triggers this flaw by sending a specially crafted request to a site using a vulnerable version of the AI ANN theme. No interaction from a logged-in user or administrative session is required; the request simply needs to reach the application. Requests that do not contain the specific, malformed serialized data will not trigger this vulnerability.

Why is this CVE concerning for public-facing websites?

Halo Surface Signal indicates that since AI ANN is a theme for web applications, it is frequently deployed on sites accessible over the internet. This means an attacker can reach the vulnerable component remotely without needing internal network access. If your site is public, it may be exposed to automated scanning and exploitation attempts targeting this flaw.

What are the first steps to address this vulnerability?

Start by identifying all instances of the AI ANN theme within your environment to confirm if any are running the affected versions. Once located, assess the business importance of those websites to prioritize your efforts. Coordinate with the application owners to ensure they are aware of the risk and are prepared to apply necessary security updates as they become available.

References

patchstack.com/database/wordpress/theme/ann/vulnerability/wordpress-…

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.