How severe is CVE-2026-25863?

CVE-2026-25863 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-25863 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-25863?

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-2026-25863 have an EU (EUVD) identifier?

Yes. CVE-2026-25863 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27083.

When was CVE-2026-25863 published?

CVE-2026-25863 was published on 2026-05-04 and last updated on 2026-06-17.

CVE-2026-25863

CVE-2026-25863 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. 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-1284.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27083
Weakness: CWE-1284
Published: 2026-05-04
Last modified: 2026-06-17

Description

Conditional Fields for Contact Form 7 WordPress plugin through version 2.7.2 contains an uncontrolled resource consumption vulnerability in the Wpcf7cfMailParser class where the hide_hidden_mail_fields_regex_callback() method reads an iteration count directly from user-supplied POST parameters without validation or upper bound enforcement. Unauthenticated attackers can supply an arbitrarily large integer value through the REST API endpoint to cause unbounded loop execution with multiple preg_replace() operations, exhausting server memory and crashing the PHP process.

Frequently asked questions

What is CVE-2026-25863?: Conditional Fields for Contact Form 7 WordPress plugin through version 2.7.2 contains an uncontrolled resource consumption vulnerability in the Wpcf7cfMailParser class where the hide_hidden_mail_fields_regex_callback() method reads an iteration count directly from user-supplied POST parameters without validation or upper bound enforcement. Unauthenticated attackers can supply an arbitrarily large integer value through the REST API endpoint to cause unbounded loop execution with multiple preg_replace() operations, exhausting server memory and crashing the PHP process.
How severe is CVE-2026-25863?: CVE-2026-25863 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-25863 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-25863?: 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-2026-25863 have an EU (EUVD) identifier?: Yes. CVE-2026-25863 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27083.
When was CVE-2026-25863 published?: CVE-2026-25863 was published on 2026-05-04 and last updated on 2026-06-17.

References

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