# CVE-2026-111730: P-Net buffer overflow in get_check_peer

Source: https://junglewise.ai/threats/cve-2026-111730-p-net-before-1-0-3-does-not-validate-the-lengthpeerstationname  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-29. Updated: 2026-10-29  
License: CC BY 4.0 with a link back

CVE-2026-111730 · Severity: info · Published 2026-10-29

P-Net is a Profinet network stack library used in industrial control systems and network devices. A buffer overflow vulnerability in the check peer function allows an adjacent attacker to crash the service or potentially execute arbitrary code by sending a specially crafted network packet that bypasses input validation.

Technologies: [RT-Labs P-Net](https://junglewise.ai/threats/technologies/p-net). Vendors: [RT-Labs](https://junglewise.ai/threats/vendors/rt-labs).

## Quick answers

**Is CVE-2026-111730 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-111730 being exploited in the wild.

**How severe is CVE-2026-111730?** Informational severity, published 29 October 2026.

**Which products and versions are affected?** RT-Labs P-Net before 1.0.3.

**Is there a fix for CVE-2026-111730?** Yes: fixed in P-Net 1.0.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-111730 attacked?** It is attacked from the adjacent network or over the network, in a software library.

**Am I affected by CVE-2026-111730?** Check whether you run RT-Labs P-Net 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 P-Net 1.0.3 or later

## Technical details

The get_check_peer() function fails to properly validate the LengthPeerStationName field in a CheckPeers block, allowing up to 255 bytes to be written into a 241-byte buffer. An attacker with adjacent network access who can establish a Profinet session can trigger a stack-based buffer overflow that writes 15 bytes past the buffer boundary, corrupting adjacent memory and potentially achieving code execution.

## Affected products

- RT Labs P-Net before 1.0.3

## Timeline

- 2026-10-29: disclosed

## References

- [https://rt-labs.com/wp-content/uploads/2026/10/RRTL-261019-01.pdf](https://rt-labs.com/wp-content/uploads/2026/10/RRTL-261019-01.pdf)

## Related threats

- [P-Net buffer over-read in DCP message processing](https://junglewise.ai/threats/cve-2026-115795-p-net-before-1-0-3-does-not-check-that-a-complete-block-header)
- [P-Net buffer over-read in RTA alarm callback](https://junglewise.ai/threats/cve-2026-115794-p-net-before-1-0-3-passes-the-application-alarm-callback-a-data)
- [P-Net RPC session leak leading to denial of service](https://junglewise.ai/threats/cve-2026-115793-p-net-before-1-0-3-does-not-release-the-rpc-session-allocated)
- [P-Net resource exhaustion via malformed RPC requests](https://junglewise.ai/threats/cve-2026-112200-p-net-before-1-0-3-does-not-release-the-application-relationship)
- [P-Net NULL pointer dereference in implicit read request handling](https://junglewise.ai/threats/cve-2026-111736-p-net-before-1-0-3-dereferences-a-null-ar-pointer-in-pf-fspm-cm)