WordPress FormGent Plugin Unauthenticated File Deletion Flaw

The FormGent plugin for WordPress is vulnerable to unauthorized arbitrary file deletion due to a missing capability check on the /wp-json/formgent/responses/attachments REST API endpoint in all versions up to, and including, 1.9.2 This is due to the REST API route being registered without any authentication middleware in routes/rest/api.php. This makes it possible for unauthenticated attackers to delete arbitrary files within the formgent uploads directory. Additionally, on Linux servers where the wp-content/uploads/formgent directory does not yet exist (the default state after plugin installation), the path traversal protection can be bypassed, enabling deletion of arbitrary files including wp-config.php which can lead to complete site takeover via a fresh WordPress installation.

Casky was already ahead

This CVE exploits attack patterns that Casky's 283matched skills already investigate — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

The FormGent WordPress plugin versions up to 1.9.2 contain a critical vulnerability (CVE-2026-3141, CVSS 9.1) that allows unauthenticated attackers to delete arbitrary files from the server. The flaw stems from a missing capability check on the REST API endpoint /wp-json/formgent/responses/attachments, which is registered without authentication middleware in routes/rest/api.php. This exposes any WordPress site running the vulnerable plugin to complete file system destruction within the FormGent uploads directory and potentially beyond on Linux systems. Any organization using this plugin to handle form submissions and file uploads faces immediate risk of data loss, service disruption, and potential secondary attacks leveraging the deletion capability.

Casky's 283 matched security skills leverage Claude AI's extended reasoning to detect the attack patterns mapped to MITRE ATT&CK techniques TA0004 (Privilege Escalation) and TA0006 (Credential Access). Practitioners monitoring their environments will identify suspicious REST API calls to /wp-json/formgent/responses/attachments endpoints without valid authentication tokens or WordPress user sessions, followed by HTTP DELETE requests targeting attachment resources. The skills detect the absence of capability checks (CWE-862) by analyzing REST route registration patterns that bypass WordPress security hooks, correlated with unexpected file deletions in wp-content/plugins/formgent/uploads directories. Casky surfaces these attack indicators through behavioral analysis of unauthenticated API access chains, enabling practitioners to distinguish legitimate plugin function from exploitation attempts before files are irretrievably removed.

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Casky Risk Score

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EPSS Probability

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Shodan Exposure

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GreyNoise Signal

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Composite risk scoring from EPSS, CISA KEV, Shodan, and GreyNoise — 21 security APIs correlated into a single Casky Risk Score. Coming in Casky Pro. Join early access →

283 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-3141.

abusing-dpapi-for-credential-access

red teaming · high

Run

abusing-shadow-credentials-for-privesc

red teaming · high

Run

Access with Stolen Session Cookie

identity access management · low

Run

MITRE ATT&CK Techniques

TA0004 TA0006

Investigate the attack patterns behind CVE-2026-3141

Casky has 283 skills that investigate the attack patterns behind CVE-2026-3141. Run one and get CVSS-scored findings in 3 minutes.

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