External risk intelligence

Greeny Theme Object Injection Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-93940

The vulnerability affects a WordPress theme, which is a component of a web application. WordPress sites and their themes are commonly deployed as public-facing web applications accessible via the internet, making this surface frequently exposed in typical usage.

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 has been identified in the Greeny theme, a component often used in web applications, that could allow attackers to inject malicious code. This type of flaw can potentially lead to unauthorized access and control over affected systems. The primary concern is to determine if your organization utilizes this specific theme, as its exposure could present a significant risk.

Untrusted data allows code injection.
It could allow attackers full system control.
Confirm if this theme is in use.

Attack Path

How an attacker could exploit the issue

An attacker could exploit this vulnerability by sending specially crafted data to a vulnerable installation of the Greeny theme, as it allows for the deserialization of untrusted data. This could lead to the injection of malicious objects, potentially allowing the attacker to compromise the entire system.

No special access needed.
Triggered by deserializing untrusted data.
Leads to object injection and system compromise.

Live Threat

Current exploitation, exposure, and threat context

A deserialization vulnerability in the Greeny theme could allow an unauthenticated attacker to inject arbitrary objects into the system. This may occur when the theme processes untrusted data, potentially leading to the execution of malicious code or disruption of the service.

Theme object data at risk.
Via untrusted data processing.
Could lead to code execution.

Operational Fix

Recommended remediation, mitigation, and detection steps

This deserialization vulnerability in the Greeny WordPress theme impacts systems where the theme is deployed, potentially affecting application owners and the platform or infrastructure teams responsible for the web server environment. The immediate first step is to identify all instances of the Greeny theme, determine their business criticality and network exposure, and then confirm the accountable owner to initiate a remediation plan based on risk.

Theme owners should manage this issue.
Verify affected theme instances and exposure.
Plan remediation based on identified risk.

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 Greeny theme?

Greeny is a WordPress theme used to determine the visual layout and presentation of a website. Themes act as a foundational layer for site design, often incorporating specialized code to handle user data, display content, and manage interface interactions. Because it sits atop the WordPress core, it processes inputs to render pages for visitors.

What does deserialization of untrusted data mean for CVE-2026-93940?

This vulnerability, classified as CWE-502, occurs when the software takes data from an outside source and converts it into complex objects without checking if that data is safe. Because the theme trusts this input implicitly, an attacker can supply a specially formatted object that forces the application to perform unauthorized actions or run malicious code, effectively tricking the system into executing commands it shouldn't.

How is this vulnerability triggered?

An attacker triggers this by sending crafted, malicious data to an installation of the Greeny theme. The flaw requires the theme to actively process this untrusted input through its deserialization functions. It is not triggered by simply visiting the site normally; the attacker must specifically target the theme's data-processing mechanisms to inject the unauthorized objects.

Is my site at risk?

If you use the Greeny theme, your site is potentially at risk. Halo Surface Signal notes that WordPress themes are typically components of web applications that are public-facing, meaning they are frequently accessible via the internet. If your instance is reachable from the network, an attacker could attempt to send the malicious data necessary to exploit this vulnerability.

What should I do if I use Greeny?

Start by identifying all websites or staging environments where the Greeny theme is active. Once you have a list of instances, assess the business criticality of those sites and confirm who is responsible for managing them. Coordinate with your team to review the theme version and prepare a remediation plan to remove, replace, or update the affected component to eliminate the risk.

References

patchstack.com/database/wordpress/theme/greeny/vulnerability/wordpre…

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.