CVE-2026-110022 Signed plug-in validation bypass
Description
The PFI plugin framework deploys executable assemblies (DLLs) from a signed plugin package into the local plugin repository and loads them via reflection, but the deployment routine processes archive entries that were never covered by the signature verification. An unauthenticated local attacker can replace an unsigned DLL outside the signed prefix in the archive passes verification and overwrites the legitimate signed assembly at the same destination path. The plugin loader then instantiates the attacker-supplied code without any additional integrity check resulting in a full compromise of the affected systems.
CVSS 4.0 detail
Vector CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitable with local access to the machine, without an account and without any user action; an attacker can seriously compromise confidentiality, integrity or availability.
- Attack vector
- Local
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- None
- Interaction
- None
- Confidentiality
- High
- Integrity
- High
- Availability
- High
- Confidentiality of other systems
- None
- Integrity of other systems
- None
- Availability of other systems
- None
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| PLCnext Engineer 0.0 | 0.0 → < 2026.6 | 2026.6 |