Is CVE-2026-39573 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-39573 being exploited in the wild.

How severe is CVE-2026-39573?

High severity, with a CVSS score of 8.1, published 17 June 2026.

Is there a fix for CVE-2026-39573?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-39573 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-39573?

Check whether you run Select-Themes Mildhill at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-39573: Select-Themes Mildhill PHP object injection

CVE-2026-39573 · Severity: high · CVSS 8.1 · Published 2026-06-17

The Mildhill theme for WordPress is vulnerable to a security flaw that allows unauthorized users to inject malicious code into a website. This could lead to complete site takeover, data theft, or service disruption. Website owners should update the theme to version 1.6 immediately to protect their operations and customer data.

Vendors: Select-Themes.

Quick answers

Is CVE-2026-39573 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-39573 being exploited in the wild.
How severe is CVE-2026-39573?: High severity, with a CVSS score of 8.1, published 17 June 2026.
Which products and versions are affected?: Select-Themes Mildhill <= 1.5.
Is there a fix for CVE-2026-39573?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-39573 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-39573?: Check whether you run Select-Themes Mildhill at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A PHP Object Injection vulnerability exists in the Mildhill WordPress theme (versions <= 1.5) due to the unsafe deserialization of user-supplied data (CWE-502). An unauthenticated remote attacker can exploit this by sending specially crafted input to the application. If a suitable Property-Oriented Programming (POP) chain is present within the environment, the attacker could achieve remote code execution, perform SQL injection, or access sensitive files. The vulnerability is addressed in version 1.6.

Affected products

Select-Themes Mildhill <= 1.5

Timeline

2026-02-12: other: Reported by Denver Jackson
2026-04-08: disclosed: Initial disclosure by Patchstack
2026-06-17: advisory: NVD publication date

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.