Control RTE (SL): Incorrect Permission Assignment for Critical Resource
CVE-2025-41659 is a high-severity incorrect permission assignment for critical resource vulnerability in Control RTE (SL) from Codesys, with a CVSS 3.1 base score of 8.3 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 3.5.21.20 as the first without the flaw, so updating Control RTE (SL) to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.26% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Control RTE (SL) to 3.5.21.20 or a later version.
- Update Control RTE (for Beckhoff CX) SL to 3.5.21.20 or a later version.
- Update Control Win (SL) to 3.5.21.20 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| CODESYS | Control RTE (SL) | 0.0.0.0 up to, but not including, 3.5.21.20 | 3.5.21.20 |
| CODESYS | Control RTE (for Beckhoff CX) SL | 0.0.0.0 up to, but not including, 3.5.21.20 | 3.5.21.20 |
| CODESYS | Control Win (SL) | 0.0.0.0 up to, but not including, 3.5.21.20 | 3.5.21.20 |
| CODESYS | HMI (SL) | 0.0.0.0 up to, but not including, 3.5.21.20 | 3.5.21.20 |
| CODESYS | Runtime Toolkit | 0.0.0.0 up to, but not including, 3.5.21.20 | 3.5.21.20 |
| CODESYS | Control for BeagleBone SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for emPC-A/iMX6 SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for IOT2000 SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for Linux ARM SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for Linux SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for PFC100 SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for PFC200 SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for PLCnext SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for Raspberry Pi SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Control for WAGO Touch Panels 600 SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
| CODESYS | Virtual Control SL | 0.0.0.0 up to, but not including, 4.17.0.0 | 4.17.0.0 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L. Scored by CNA (cert.vde.com).
Official description
A low-privileged attacker can remotely access the PKI folder of the CODESYS Control runtime system and thus read and write certificates and its keys. This allows sensitive data to be extracted or to accept certificates as trusted. Although all services remain available, only unencrypted communication is possible if the certificates are deleted.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Permission Assignment for Critical Resource
The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
How developers prevent this class of flaw
- When using a critical resource such as a configuration file, check to see if the resource has insecure permissions (such as being modifiable by any regular user), and generate an error or even exit the software if there is a possibility that the resource could have been modified by an unauthorized party.
- Divide the software into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully defining distinct user groups, privileges, and/or roles. Map these against data, functionality, and the related resources. Then set the permissions accordingly. This will allow you to maintain more fine-grained control over your resources.
- During program startup, explicitly set the default permissions or umask to the most restrictive setting possible. Also set the appropriate permissions during program installation. This will prevent you from inheriting insecure permissions from any user who installs or runs the program.
More Incorrect Permission Assignment for Critical Resource vulnerabilities (CWE-732)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Control RTE (SL)
- 8.1 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.8 High severity
- 7.5 High severity
Recent Incorrect Permission Assignment for Critical Resource vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.3 High severity
- 7.8 High severity
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