Critical WordPress Form Plugin Flaws Enable Unauthenticated Server Compromise
Two high-severity vulnerabilities were disclosed in widely used WordPress form plugins, exposing sites to unauthenticated attacks that can lead to full server compromise. CVE-2026-4347 affects MW WP Form through version 5.1.0 and stems from insufficient file path validation in generate_user_filepath and move_temp_file_to_upload_dir. An attacker can move arbitrary files on the server without authentication, and if a sensitive file such as wp-config.php is relocated, the flaw can be leveraged for remote code execution. Exploitation requires a form with a file upload field and the Saving inquiry data in database option enabled; the issue is tracked as CWE-22.

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3 events from the most recent confirmed update back to the earliest known activity.
Everest Forms PHP object injection disclosed as CVE-2026-3296
The Everest Forms vulnerability was newly received by security@wordfence.com as CVE-2026-3296. The flaw enables unauthenticated PHP object injection through public form fields due to unsafe use of unserialize(), potentially causing severe impact when an administrator opens stored entries.
Everest Forms fixes PHP object injection in version 3.4.4
References associated with CVE-2026-3296 indicate code changes tied to the Everest Forms 3.4.4 update, addressing unsafe deserialization of untrusted form entry metadata. The issue affects versions up to and including 3.4.3 and can be triggered by unauthenticated form submissions, with exploitation occurring when an administrator views entries.
MW WP Form arbitrary file move vulnerability disclosed as CVE-2026-4347
A vulnerability affecting MW WP Form versions up to and including 5.1.0 was newly received by security@wordfence.com. The flaw allows unauthenticated attackers to move arbitrary files via insufficient file path validation, potentially leading to remote code execution under specific configuration conditions.
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Sources
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CVE-2026-3296 - Everest Forms <= 3.4.3 - Unauthenticated PHP Object Injection via Form Entry Metadata
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Open sourceCVE-2026-5436 - MW WP Form <= 5.1.1 - Unauthenticated Arbitrary File Move via regenerate_upload_file_keys
cvefeed.io
Open sourceCVE-2026-4347 - MW WP Form <= 5.1.0 - Unauthenticated Arbitrary File Move via move_temp_file_to_upload_dir
cvefeed.io
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