CVE-2026-28167: Super Forms Path Traversal Vulnerability

CVE-2026-28167 Overview

CVE-2026-28167 is an unauthenticated arbitrary file download vulnerability affecting the Super Forms WordPress plugin in versions up to and including 6.3.315. The flaw is classified as a path traversal weakness [CWE-22], allowing remote attackers to retrieve arbitrary files from the underlying web server without authentication. Successful exploitation exposes sensitive files such as WordPress configuration data, credentials, and application source code. The vulnerability requires no user interaction and is exploitable over the network.

Critical Impact
Unauthenticated remote attackers can download arbitrary files from the server hosting Super Forms <= 6.3.315, potentially exposing wp-config.php, database credentials, and private application data.

Affected Products

Super Forms WordPress plugin versions <= 6.3.315
WordPress installations with the vulnerable plugin active
All hosting environments running the affected plugin regardless of underlying operating system

Discovery Timeline

2026-08-24 - CVE-2026-28167 published to the National Vulnerability Database
2026-08-24 - Last updated in the NVD database

Technical Details for CVE-2026-28167

Vulnerability Analysis

CVE-2026-28167 is a path traversal vulnerability that permits unauthenticated file download from the server hosting a vulnerable Super Forms installation. The plugin exposes a file-serving endpoint that does not adequately validate or canonicalize user-supplied file path parameters. Attackers submit crafted requests containing traversal sequences to escape the intended download directory and read files elsewhere on the filesystem.

The confidentiality impact is high because sensitive server-side content becomes readable to any network attacker. Integrity and availability are not directly affected, since the flaw only permits read access. However, disclosed credentials and secrets frequently enable follow-on attacks including database compromise and full site takeover.

Root Cause

The root cause is improper limitation of a pathname to a restricted directory [CWE-22]. The plugin accepts a filename or path parameter from a client request and passes it to a file-read routine without normalizing traversal sequences such as ../ or validating that the resolved path remains within an approved base directory. Missing authentication on the download handler compounds the issue, removing any access barrier prior to file retrieval.

Attack Vector

Exploitation occurs over the network against the plugin's public-facing endpoint. An attacker issues an HTTP request to the vulnerable Super Forms file-download handler with a path parameter referencing a target file outside the intended directory. Because no authentication is required, mass scanning and opportunistic exploitation are practical. Refer to the Patchstack Vulnerability Report for endpoint and parameter specifics.

No verified proof-of-concept code is published in the enriched CVE data, so exploitation is described in prose rather than reproduced here.

Detection Methods for CVE-2026-28167

Indicators of Compromise

HTTP requests to Super Forms plugin endpoints containing traversal sequences such as ../, ..%2f, or URL-encoded variants in query or body parameters
Web server access logs showing successful responses (HTTP 200) to plugin download handlers with unusual file parameter values
Outbound egress requests referencing plugin paths under /wp-content/plugins/super-forms/ combined with filename parameters pointing to system files
Unexpected access to wp-config.php, .env, or /etc/passwd reflected in application or web server telemetry

Detection Strategies

Deploy WAF rules that inspect requests to Super Forms endpoints for path traversal patterns and encoded traversal sequences
Alert on anonymous requests to plugin file-handling endpoints that return file content larger than expected baselines
Correlate WordPress access logs with filesystem read events on sensitive configuration files

Monitoring Recommendations

Ingest WordPress web server logs into a centralized logging platform and retain them for at least 90 days for retrospective hunting
Baseline normal request patterns to /wp-content/plugins/super-forms/ and alert on statistical anomalies in parameter values or request frequency
Monitor for read access to secrets files such as wp-config.php, backup archives, and private key material by the web server user

How to Mitigate CVE-2026-28167

Immediate Actions Required

Upgrade Super Forms to a version later than 6.3.315 once a fixed release is available from the vendor
Disable or remove the Super Forms plugin from production WordPress sites until a patched version is installed
Rotate any credentials, API keys, and secrets stored in wp-config.php or related configuration files that may have been exposed
Audit web server and application logs for prior exploitation attempts using the indicators described above

Patch Information

Consult the Patchstack Vulnerability Report for the authoritative fixed version and vendor advisory. Apply the vendor-supplied update through the WordPress plugin management console once released, and verify the installed version against the fixed release notes.

Workarounds

Block or restrict access to Super Forms plugin file-download endpoints at the WAF or reverse proxy layer until the plugin is updated
Enforce filesystem permissions that prevent the web server user from reading sensitive files such as wp-config.php beyond what WordPress requires
Apply virtual patching rules that reject requests containing traversal sequences (../, ..%2f, %2e%2e/) targeting the plugin path

bash

# Example nginx rule to block traversal patterns targeting Super Forms
location ~* /wp-content/plugins/super-forms/ {
    if ($args ~* "(\.\./|\.\.%2f|%2e%2e/)") {
        return 403;
    }
}