Premmerce Dev Tools: Unrestricted Upload of File with Dangerous Type
CVE-2026-6933 is a high-severity unrestricted upload of file with dangerous type vulnerability in Premmerce Dev Tools from Premmerce, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Premmerce Dev Tools versions: 2.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.85% chance of exploitation within 30 days, higher than 59% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Premmerce Dev Tools you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Premmerce | Premmerce Dev Tools | 2.0 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (wordfence.com).
Official description
The Premmerce Dev Tools plugin for WordPress is vulnerable to Remote Code Execution via missing authorization in versions up to and including 2.0. This is due to the 'generatePluginHandler' function lacking any authorization check before processing user-supplied POST data, combined with the 'createFromStub' function performing unsanitized string substitution of the 'premmerce_plugin_namespace' parameter directly into PHP stub files written to the wp-content/plugins/ directory. An attacker can inject a semicolon followed by arbitrary PHP code into the namespace parameter, causing the generated plugin file to contain and execute that code when accessed via HTTP. This makes it possible for authenticated attackers with Subscriber-level access and above to create arbitrary PHP files on the server and achieve remote code execution.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Unrestricted Upload of File with Dangerous Type
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
How developers prevent this class of flaw
- Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.
More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/tags/2.0/src/Admin/Admin.php#L107
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/tags/2.0/src/PluginGenerator/PluginData.php#L97
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/tags/2.0/src/PluginGenerator/PluginGenerator.php#L125
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/trunk/src/Admin/Admin.php#L107
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/trunk/src/PluginGenerator/PluginData.php#L97
- plugins.trac.wordpress.org/browser/premmerce-dev-tools/trunk/src/PluginGenerator/PluginGenerator.php#L125
- wordfence.com/threat-intel/vulnerabilities/id/c43c060b-7a18-49ee-a753-ae1ed2f7e04d?source=cve
Recent Unrestricted Upload of File with Dangerous Type vulnerabilities
- 9.9 Critical severity
- 9.3 Critical severity
- 8.7 High severity
- 9.8 Critical severity
- 9.9 Critical severity
- 9.8 Critical severity
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