SECURELYN

CVE-2026-56660

GetSimple CMS is a content management system (CMS), and GetSimple CMS CE is the community edition of that CMS. Prior to version 1.5, the update handler in UpdateCE.php downloads a ZIP archive and extracts its contents into the web root without validating file types or extraction paths. Because PHP files are written into a web-accessible directory, an attacker who can cause a malicious archive to be processed achieves remote code execution as the web-server user. Entry names are also used unsafely, allowing directory traversal (../) to write files outside the intended extraction directory. Thi…

Scores

9.1
CVSS 9.1 out of 10, critical severity.
0.5%
EPSS 0.5% chance of exploitation in the next 30 days.

The facts

Published
1 October 2026
Last changed
1 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.1 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.5% chance of exploitation activity in the next 30 days (percentile 43).

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References