CI4MS: Methods Management Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS

Exploitation

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

CVSS

9.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L

EPSS

• CVE-2026-34558: 0.32% estimated exploitation activity in the next 30 days; percentile 24.93 (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 Vulnerability: Stored DOM XSS via Methods Management Fields (Global Persistent Payload Execution) - Stored Cross-Site Scripting via Unsanitized Method Creation and Management Inputs - Automatic Execution Across All Pages Where Method Is Rendered in Navigation Description The application fails to properly sanitize user-controlled input within the Methods Management functionality when creating or managing application methods/pages. Multiple input fields accept attacker-controlled JavaScript payloads that are stored server-side without sanitization or output encoding. These stored values are later rendered directly into administrative interfaces and global navigation components without proper encoding, resulting in Stored DOM-Based Cross-Site Scripting (XSS). Critically, because created methods are automatically rendered inside the system’s navigation/menu structure, the injected payload executes globally — meaning every page visited where the malicious method appears in the…

Published by the source

1 Apr 2026, 00:09 UTC

Last modified by the source

1 Apr 2026, 00:09 UTC

Source last checked

26 Oct 2026, 14:39 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-v77r-xg3p-75g7

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# Patch Next advisory brief: CVE-2026-34558

Advisory: CI4MS: Methods Management Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS
IDs: CVE-2026-34558, GHSA-v77r-xg3p-75g7
Record: https://patchnext.com/advisories/cve-2026-34558 (revision 1, source checked 26 Oct 2026, 14:39 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.1)
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 0.31.0.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist ci4-cms-erp/ci4ms: affected <= 0.28.6.0; fixed in 0.31.0.0

## 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-v77r-xg3p-75g7 (GitHub-reviewed advisory GHSA-v77r-xg3p-75g7 lists affected ranges: Packagist ci4-cms-erp/ci4ms >=0 <=0.28.6.0)

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