# CVE-2026-85114: Siemens .NET Client Library for SIMATIC S7 Webserver API path traversal

Source: https://junglewise.ai/threats/cve-2026-85114-a-vulnerability-has-been-identified-in-net-client-library-for  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-13. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-85114 · Severity: high · CVSS 7.5 · Published 2026-10-13

The .NET Client Library for SIMATIC S7 Webserver API is used by industrial applications to communicate with Siemens SIMATIC S7 controllers. A path traversal vulnerability in filename validation allows an attacker to write arbitrary files outside the intended directory, potentially overwriting critical application files and compromising system integrity.

Vendors: [Siemens](https://junglewise.ai/threats/vendors/siemens).

## Quick answers

**Is CVE-2026-85114 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-85114 being exploited in the wild.

**How severe is CVE-2026-85114?** High severity, with a CVSS score of 7.5, published 13 October 2026.

**Which products and versions are affected?** Siemens .NET Client Library for SIMATIC S7 Webserver API All versions < V3.3.61.

**Is there a fix for CVE-2026-85114?** Yes: fixed in V3.3.61 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-85114 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-85114?** Check whether you run Siemens .NET Client Library for SIMATIC S7 Webserver API at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in V3.3.61 or later

## Technical details

The vulnerability exists in ticket download functionality, where the application fails to properly validate filenames received from remote servers (CWE-22). An unauthenticated remote attacker can manipulate the ticket response to include path traversal sequences, allowing arbitrary file write operations outside the intended download directory. If file overwriting is enabled, this permits replacement of existing files accessible to the application.

## Affected products

- Siemens .NET Client Library for SIMATIC S7 Webserver API All versions < V3.3.61

## Identifiers

- CVE-2026-85114
- CVE-2026-85115

## Timeline

- 2026-10-13: disclosed

## References

- [https://cert-portal.siemens.com/productcert/html/ssa-390352.html](https://cert-portal.siemens.com/productcert/html/ssa-390352.html)

## Related threats

- [Siemens .NET Client Library SIMATIC S7 Webserver API information disclosure](https://junglewise.ai/threats/cve-2026-85115-a-vulnerability-has-been-identified-in-net-client-library-for)