SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-56660

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.

CRITICAL 9.1EPSS 0.53%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.53%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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. This issue has been patched in version 1.5.

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS
0.53% probability · 44th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-352, CWE-434, CWE-918
Source
security-advisories@github.com
EPSS trend
0%3%5%2 October 2026: 0.53%26 October 2026: 0.53%2 October 202626 October 2026

EPSS moved from 0.5% on 2 October 2026 to 0.5% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.