# CVE-2026-115794: P-Net buffer over-read in RTA alarm callback

Source: https://junglewise.ai/threats/cve-2026-115794-p-net-before-1-0-3-passes-the-application-alarm-callback-a-data  
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-2026-115794 · Severity: info · Published 2026-10-29

P-Net is a real-time communication library used in industrial automation systems. A vulnerability allows an attacker with adjacent network access to send a malformed alarm frame that causes applications to read beyond the bounds of a receive buffer, potentially exposing memory contents. Applications that do not use alarm data are not affected.

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-2026-115794 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-115794 being exploited in the wild.

**How severe is CVE-2026-115794?** 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-2026-115794?** Yes: fixed in 1.0.3. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-115794 attacked?** It is attacked from the adjacent network, in a software library.

**Am I affected by CVE-2026-115794?** 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 1.0.3

## Technical details

The vulnerability is a buffer over-read in the alarm callback handler. When processing an RTA alarm frame, P-Net passes the application a data length taken from the variable part length field without validating it against the actual received frame size. An attacker with an established Application Relationship and adjacent network access can send a short frame with an inflated length field, causing the application to read up to 65507 bytes past the buffer end. Only applications that process the alarm data are affected.

## 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 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)
- [P-Net integer underflow in pf_cpm_c_data_ind()](https://junglewise.ai/threats/cve-2026-111735-p-net-before-1-0-3-contains-an-integer-underflow-in-pf-cpm-c)