CI4MS has Unrestricted PHP File Upload via Theme Installation that Leads to Authenticated Remote Code Execution

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.6 · CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-41587: 0.62% estimated exploitation activity in the next 30 days; percentile 49.94 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A theme upload feature allows any authenticated backend user with theme-upload permission to achieve remote code execution (RCE) by uploading a crafted ZIP file. PHP files inside the ZIP are installed into the web-accessible public/ directory with no extension or content filtering, making them directly executable via HTTP. Details File: modules/Theme/Controllers/Theme.php After a ZIP is uploaded and extracted to a temporary directory, installthemefromtmp() is called unconditionally: Theme.php:51-52 File: modules/Theme/Helpers/themeshelper.php The helper copies every file matching . from public/templates/<name/ inside the ZIP directly into public/templates/<name/ on disk using rename(), with no file-extension allowlist, no MIME check, and no content inspection: themeshelper.php:60-68 Because the web root is public/, any .php file placed there is directly reachable over HTTP. PHP files are also installed — without filtering — into app/Controllers/templates/<name/,…

Published by the source

29 Apr 2026, 20:42 UTC

Last modified by the source

8 May 2026, 19:55 UTC

Source last checked

26 Oct 2026, 14:40 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-fw49-9xq4-gmx6

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# Patch Next advisory brief: CVE-2026-41587

Advisory: CI4MS has Unrestricted PHP File Upload via Theme Installation that Leads to Authenticated Remote Code Execution
IDs: CVE-2026-41587, GHSA-fw49-9xq4-gmx6
Record: https://patchnext.com/advisories/cve-2026-41587 (revision 1, source checked 26 Oct 2026, 14:40 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: ci4-cms-erp/ci4ms 0.31.7.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist ci4-cms-erp/ci4ms: affected >= 0.26.0.0, <= 0.31.6.0; fixed in 0.31.7.0

## Suggested inspection (read-only)
- Packagist ci4-cms-erp/ci4ms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on ci4-cms-erp/ci4ms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-fw49-9xq4-gmx6 (GitHub-reviewed advisory GHSA-fw49-9xq4-gmx6 lists affected ranges: Packagist ci4-cms-erp/ci4ms >=0.26.0.0 <=0.31.6.0)

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