Quick answers
- Is CVE-2026-40759 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-40759 being exploited in the wild.
- How severe is CVE-2026-40759?
- High severity, with a CVSS score of 8.1, published 17 June 2026.
- Which products and versions are affected?
- Mikado-Themes Esmée <= 1.4.
- Is there a fix for CVE-2026-40759?
- 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-2026-40759 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-40759?
- Check whether you run Mikado-Themes Esmée 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 (CWE-502) exists in the Esmée WordPress theme versions up to and including 1.4. The flaw stems from the deserialization of untrusted data, which allows an unauthenticated attacker to inject PHP objects. If a suitable Property-Oriented Programming (POP) chain is present in the environment, this can lead to remote code execution, SQL injection, or arbitrary file deletion. The attack can be performed over the network without any user interaction, though the complexity is rated as high. Users are advised to update to version 1.5 or later to remediate the issue.
Affected products
- Mikado-Themes Esmée <= 1.4
Timeline
- 2026-02-24: other: Reported by Denver Jackson
- 2026-04-20: disclosed: Vulnerability published by Patchstack
- 2026-06-17: advisory: CVE published in NVD