Is CVE-2026-18644 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-18644 being exploited in the wild.

How severe is CVE-2026-18644?

Medium severity, with a CVSS score of 5.4, published 3 August 2026.

Is there a fix for CVE-2026-18644?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-18644 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-18644?

Check whether you run Danpros HTMLy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-18644: danpros HTMLy path traversal in Delete Username Endpoint

CVE-2026-18644 · Severity: medium · CVSS 5.4 · Published 2026-08-03

HTMLy is a flat-file blogging platform (CMS) that does not require a database. An authenticated administrator can exploit a path traversal vulnerability in the user deletion function to delete arbitrary files on the server. An attacker with admin credentials could delete critical configuration files, causing application outage, or remove other important system files, leading to data loss or further system compromise.

Technologies: Danpros HTMLy. Vendors: Danpros.

Quick answers

Is CVE-2026-18644 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-18644 being exploited in the wild.
How severe is CVE-2026-18644?: Medium severity, with a CVSS score of 5.4, published 3 August 2026.
Which products and versions are affected?: Danpros HTMLy up to 3.1.1.
Is there a fix for CVE-2026-18644?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-18644 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-18644?: Check whether you run Danpros HTMLy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A path traversal vulnerability (CWE-22) exists in the /admin/users/:username/delete POST handler in /system/htmly.php. The handler receives a file parameter from the HTTP request and passes it directly to PHP's unlink() function without any sanitization, realpath() validation, basename() extraction, or path filtering. An authenticated administrator with a valid CSRF token can supply an arbitrary absolute or relative file path to delete any file writable by the PHP process. The attack requires prior admin authentication and a valid CSRF token; no fix has been announced by the vendor.

Affected products

danpros HTMLy up to 3.1.1

Timeline

2026-06-10: disclosed
2026-08-03: advisory

References

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