tomdever wpForo Forum Plugin up to 3.0.2 on WordPress topic_add body file inclusion

Summaryinfo

A vulnerability categorized as critical has been discovered in tomdever wpForo Forum Plugin up to 3.0.2 on WordPress. This affects the function topic_add. Executing a manipulation of the argument body can lead to file inclusion. This vulnerability is registered as CVE-2026-5809. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in tomdever wpForo Forum Plugin up to 3.0.2 on WordPress and classified as critical. This vulnerability affects the function topic_add. The manipulation of the argument body with an unknown input leads to a file inclusion vulnerability. The CWE definition for the vulnerability is CWE-73. The product allows user input to control or influence paths or file names that are used in filesystem operations. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was published by Leonid Semenenko. The advisory is shared for download at wordfence.com. This vulnerability was named CVE-2026-5809 since 04/08/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available.

Upgrading to version 3.0.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-21676). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Forum Software

Vendor

• tomdever

Name

• wpForo Forum Plugin

Version

• 3.0.0
• 3.0.1
• 3.0.2

CPE 2.3info

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CPE 2.2info

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Once again VulDB remains the best source for vulnerability data.

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