CVE-2026-15748

What is known

The Forminator Forms plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.56.1 via the handle_file_upload function. This is due to insufficient file type validation in handle_file_upload, where the dangerous-extension blocklist performs exact-key matching that is bypassed by pipe-alternative MIME type keys, combined with a public submission handler that trusts attacker-controlled upload field configuration injected via a forged Select field value. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible.

Business impact

Successful exploitation of CVE-2026-15748, a critical vulnerability (CVSS 9.8) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

• NVD
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