PhastPress: Filesystem traversal

PhastPress is affected by filesystem traversal. The vulnerable path is reachable without authentication. A crafted path can escape the intended directory and reach files or directories elsewhere on the server.

CVE / CNA score 9.8 CVSS 3.1 · security@wordfence.com

NVD score Pending NVD has not published its own CVSS assessment.

Component: PhastPress
Plugin slug: phastpress
Affected: See vendor advisory
Safe version: See mitigation notes
Published: Dec 23, 2025
Weakness: CWE-158 — Improper Neutralization of Null Byte or NUL Character

This CVE was published Dec 23, 2025 and is one of 2 known issues for this plugin.

What to do

Update, patch or deactivate.

Update PhastPress to a release outside the affected range, or disable and remove it until a fixed version is available.

No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Source record

Technical description

The PhastPress plugin for WordPress is vulnerable to Unauthenticated Arbitrary File Read via null byte injection in all versions up to, and including, 3.7. This is due to a discrepancy between the extension validation in `getExtensionForURL()` which operates on URL-decoded paths, and `appendNormalized()` which strips everything after a null byte before constructing the filesystem path. This makes it possible for unauthenticated attackers to read arbitrary files from the webroot, including wp-config.php, by appending a double URL-encoded null byte (%2500) followed by an allowed extension (.txt) to the file path.

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

References

Update, patch or deactivate.

Technical description

Primary and upstream sources