VulnerabilityPublished 11 Apr 2026Updated 13 Apr 2026

CVE-2026-5809: wpForo Forum (WordPress plugin) · External Control of File Name or Path

Affects wpForo Forum (WordPress plugin)Source CVE Database V5

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Not known to be exploited · CVSS 7.1 High.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.1High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 42% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
tomdeverwpForo Forum	Affected <=3.0.2	Fixed in–

AI-suggested

Until an official fix is released, restrict user roles and permissions to trusted users only, and consider disabling or limiting access to the wpForo Forum plugin's topic editing features for lower-privileged users. Monitor for updates from the vendor and apply patches promptly when available.

Description

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.

Impact

An attacker with subscriber-level or higher access can delete arbitrary files on the server that are writable by the PHP process. This includes critical files such as wp-config.php, which could disrupt the WordPress site's operation or lead to denial of service. The vulnerability does not directly disclose information or allow code execution but impacts availability by file deletion.

Summary

CVE-2026-5809 is an Arbitrary File Deletion vulnerability in the wpForo Forum WordPress plugin (versions up to 3.0.2). The issue arises because the topic_add() and topic_edit() handlers accept arbitrary arrays from $_REQUEST and store them as postmeta without restricting which fields can contain arrays. The 'body' field allows an attacker to supply a file path via data[body][fileurl], which is stored in the database. Later, when the attacker triggers a delete action with wpftcf_delete[]=body, the plugin retrieves the stored file path and calls wp_delete_file() on it without proper validation or sanitization. This enables authenticated users with low privileges to delete arbitrary files writable by the PHP process, potentially impacting site availability and configuration.

CWE-73External Control of File Name or Path (opens in a new tab)
Base weaknessLikelihood of exploit: HighOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product allows user input to control or influence paths or file names that are used in filesystem operations.
Architecture and Design
When the set of filenames is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames, and reject all other inputs. For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt".
Architecture and Design · Operation
Run your code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict all access to files within a particular directory.
Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks…
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V12.3.2 (opens in a new tab)
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
Attack patterns
Subverting Environment Variable Values (opens in a new tab)
Leverage Alternate Encoding (opens in a new tab)
Using Slashes and URL Encoding Combined to Bypass Validation Logic (opens in a new tab)
URL Encoding (opens in a new tab)
Manipulating Web Input to File System Calls (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 18 Apr 2026, 14:38 UTC

WeaknessesCWE-73

Technical details

References

Community reviews

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