Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-66583 – Unauthenticated PHP Object Injection – Forminator (WordPress plugin) ≤ 1.57.0

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-66583 is a critical unauthenticated PHP Object Injection (deserialization of untrusted data, CWE-502) vulnerability in the Forminator WordPress plugin, affecting all versions up to and including 1.57.0. The flaw carries a CVSS v3.1 base score of 9.8 (Critical) and can be triggered remotely without authentication or user interaction, and if a usable POP (Property-Oriented Programming) chain is present on the target site, it can lead to code injection, SQL injection, path traversal, or denial of service.

Technical details

  • Root cause: unsafe deserialization of untrusted, attacker-supplied input within the Forminator plugin (CWE-502, CAPEC-586 Object Injection).
  • Trigger conditions: an unauthenticated attacker sends a crafted request containing a serialized PHP object to a vulnerable endpoint exposed by the plugin.
  • Attack vector: Network — no authentication or user interaction required, low attack complexity.
  • Impact: on its own, object injection can be used for denial of service; if a compatible POP/gadget chain exists on the site (via Forminator itself or another installed plugin/theme), impact can escalate to remote code execution, SQL injection, or path traversal, with full compromise of confidentiality, integrity, and availability.

Affected software

  • WPMU DEV Forminator (WordPress plugin) — versions up to and including 1.57.0
  • Fixed in version 1.57.1 and later

Severity

  • CVSS v3.1 Base Score: 9.8 (Critical)
  • Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Mitigation and recommended actions

  • Immediate: Update the Forminator plugin to version 1.57.1 or later.
  • If unable to patch immediately: restrict or monitor unauthenticated access to Forminator endpoints via a WAF, and audit installed plugins/themes for known deserialization gadget chains that could be chained with this issue; disable or remove the Forminator plugin until it can be patched.

How IONIX identifies potentially affected assets

IONIX matches the following signals against data already collected when it crawled the asset; identifying the technology sends no request beyond that crawl.

  • Raw HTTP response body: /wp-content/plugins/forminator/

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge