CVE-2026-5809

CVE-2026-5809: high vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-5809CVSS 7.1Web

CVE-2026-5809

CVE-2026-5809: high vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
7.1 HIGH
EPSS
39.85%
Known exploited
not in KEV
Product
-

What is known

The wpForo Forum plugin for WordPress is vulnerable to Arbitrary File Deletion in versions up to and including 3.0.2. This is due to a two-step logic flaw: the topic_add() and topic_edit() action handlers accept arbitrary user-supplied data[*] arrays from $_REQUEST and store them as postmeta without restricting which fields may contain array values. Because 'body' is included in the allowed topic fields list, an attacker can supply data[body][fileurl] with an arbitrary file path (e.g., wp-config.php or an absolute server path). This poisoned fileurl is persisted to the plugin's custom postmeta database table. Subsequently, when the attacker submits wpftcf_delete[]=body on a topic_edit request, the add_file() method retrieves the stored postmeta record, extracts the attacker-controlled fileurl, passes it through wpforo_fix_upload_dir() which only rewrites legitimate wpforo upload paths and returns all other paths unchanged, and then calls wp_delete_file() on the unvalidated path. This makes it possible for authenticated attackers, with subscriber-level access and above, to delete arbitrary files writable by the PHP process on the server, including critical files such as wp-config.

Business impact

Successful exploitation of CVE-2026-5809, a high vulnerability (CVSS 7.1) 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

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