How severe is CVE-2026-40757?

CVE-2026-40757 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-40757 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40757?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-40757 have an EU (EUVD) identifier?

Yes. CVE-2026-40757 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37697.

When was CVE-2026-40757 published?

CVE-2026-40757 was published on 2026-06-17.

CVE-2026-40757

CVE-2026-40757 is a high-severity vulnerability with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-502.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37697
Weakness: CWE-502
Published: 2026-06-17
Last modified: 2026-06-17

Description

Unauthenticated PHP Object Injection in Château <= 1.2.1 versions.

Frequently asked questions

What is CVE-2026-40757?: Unauthenticated PHP Object Injection in Château <= 1.2.1 versions.
How severe is CVE-2026-40757?: CVE-2026-40757 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-40757 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40757?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-40757 have an EU (EUVD) identifier?: Yes. CVE-2026-40757 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37697.
When was CVE-2026-40757 published?: CVE-2026-40757 was published on 2026-06-17.

References

https://patchstack.com/database/wordpress/theme/chateau/vulnerability/wordpress-chateau-theme-1-2-1-php-object-injection-vulnerability?_s_id=cve

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