CVE-2026-56053 - Vulnerability Details

Description

Subscriber PHP Object Injection in EventPrime <= 4.3.4.1 versions.

Published: 2026-06-25

Score: 8.8 High

EPSS: n/a

KEV: No

Impact:

Action:

Analysis

Impact

EventPrime plugin versions up to 4.3.4.1 allow PHP Object Injection, a flaw where arbitrary PHP objects can be deserialized from untrusted input. The vulnerability is a CWE‑502 weakness that can enable attackers to execute arbitrary code, modify data, or gain elevated privileges once the plugin processes malicious serialized payloads.

Affected Systems

Any WordPress installation running the EventPrime plugin by EventPrime, in versions 4.3.4.1 or earlier.

Risk and Exploitability

The flaw scores 8.8 on CVSS, indicating high severity. No EPSS data is available, so exploitation likelihood cannot be quantified, and the vulnerability is not yet listed in CISA KEV. Based on the description, it is inferred that the attack vector involves an authenticated user with access to the subscriber component who can supply crafted serialized data to trigger the injection.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

EventPrime

unaffected

Version	Status	Constraints
`n/a`	affected	≤ 4.3.4.1

No data.

No data available yet.

Remediation

Vendor Solution

Update the WordPress EventPrime Plugin to the latest available version (at least 4.3.4.2).

OpenCVE Recommended Actions

Upgrade the EventPrime WordPress plugin to version 4.3.4.2 or later.
If the EventPrime plugin is not required for your site's functionality, uninstall it completely from the WordPress installation.
Restrict access to the subscriber functionality to trusted administrators only and ensure that no unauthenticated or low‑privilege users can supply serialized data to the plugin.

Generated by OpenCVE AI on June 25, 2026 at 16:18 UTC.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://patchstack.com/database/wordpress/plugin/eventprime-event-calendar-management/vulnerability/wordpress-eventprime-plugin-4-3-4-1-php-object-injection-vulnerability?_s_id=cve

History

Thu, 25 Jun 2026 14:00:00 +0000

Type	Values Removed	Values Added
Description		Subscriber PHP Object Injection in EventPrime <= 4.3.4.1 versions.
Title		WordPress EventPrime plugin <= 4.3.4.1 - PHP Object Injection vulnerability
Weaknesses		CWE-502
References		https://patchstack.com/database/wordpress/plugin/eventprime-event-calendar-management/vulnerability/wordpress-eventprime-plugin-4-3-4-1-php-object-injection-vulnerability?_s_id=cve
Metrics		cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}`

Subscriptions

No data.

MITRE

Status: PUBLISHED

Assigner: Patchstack

Published: 2026-06-25T13:12:42.844Z

Updated: 2026-06-25T23:23:16.436Z

Reserved: 2026-06-18T14:38:04.420Z

Link: CVE-2026-56053

Vulnrichment

No data.

NVD

No data.

Redhat

No data.

OpenCVE Enrichment

Updated: 2026-06-25T16:30:15Z

Weaknesses

CWE-502
Deserialization of Untrusted Data

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Impact

Affected Systems

Risk and Exploitability

Tracking

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

Subscriptions

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