---
id: CVE-2026-110021
title: Missing GSDX SignatureValue verification
summary: >-
  PLCnext Engineer checks GSDX manifest reference digests but does not
  cryptographically verify the XML `SignatureValue` over canonicalized
  `SignedInfo`. An unauthenticated local attacker can modify signed GSDML
  content, update its manifes…
severity: medium
cvss: 6.2
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-347
vendor: Phoenix Contact
product: PLCnext Engineer
affected:
  - plcnext_engineer >= 0.0 < 2026.6
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-04T20:09:18.085257Z'
published: '2026-11-04'
updated: '2026-11-04'
sourceUpdated: '2026-11-04T20:09:40.784Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-110021'
references:
  - url: 'https://www.certvde.com/en/advisories/VDE-2026-121/'
tags:
  - cve.org
epss: 0.00062
epssPercentile: 0.00008
ingestedAt: '2026-11-05T21:36:00.531Z'
---

## Overview

PLCnext Engineer checks GSDX manifest reference digests but does not cryptographically verify the XML `SignatureValue` over canonicalized `SignedInfo`. An unauthenticated local attacker can modify signed GSDML content, update its manifest digest, retain the public certificate data, and leave an invalid nonempty `SignatureValue`. PLCnext Engineer prior to 2026.6 reports the package as `Valid` and selects the modified device description for import under the default policy.

## Affected

- `plcnext_engineer >= 0.0 < 2026.6`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.