# CVE-2026-38719: EIPStackGroup OpENer out-of-bounds read in CPF parser

Source: https://junglewise.ai/threats/cve-2026-38719-eipstackgroup-opener-out-of-bounds-read-in-cpf-parser  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-18. Updated: 2026-05-18  
License: CC BY 4.0 with a link back

CVE-2026-38719 · Severity: medium · CVSS 6.2 · Published 2026-05-18

OpENer is an open-source software stack used by industrial devices to communicate over EtherNet/IP networks. A security flaw in how the software handles incoming data packets could allow an attacker to crash the device by sending a specially crafted message. This could lead to a loss of communication or control in industrial environments, potentially disrupting operations.

Technologies: [EIPStackGroup OpENer](https://junglewise.ai/threats/technologies/opener). Vendors: [EIPStackGroup](https://junglewise.ai/threats/vendors/eipstackgroup).

## Quick answers

**Is CVE-2026-38719 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-38719 being exploited in the wild.

**How severe is CVE-2026-38719?** Medium severity, with a CVSS score of 6.2, published 18 May 2026.

**Which products and versions are affected?** EIPStackGroup OpENer v2.3-558-g1e99582.

**Is there a fix for CVE-2026-38719?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-38719 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-38719?** Check whether you run EIPStackGroup OpENer 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.

## Technical details

An out-of-bounds read vulnerability exists in the CreateCommonPacketFormatStructure() function within source/src/enet_encap/cpf.c of OpENer. The vulnerability is caused by insufficient validation of the 'item_count' field in the Common Packet Format (CPF) header against the actual length of the data slice. An attacker can provide a large, malicious item_count value, causing the parser to continue reading structured fields beyond the allocated buffer (cpf_start + data_length). While the CVSS vector provided by CISA-ADP suggests a local attack vector (AV:L), the component is part of a network encapsulation layer (ENIP/CPF), typically reachable over the network. Exploitation leads to a denial-of-service (crash) via a heap-buffer-overflow.

## Affected products

- EIPStackGroup OpENer v2.3-558-g1e99582

## Timeline

- 2026-03-25: other: Issue reported on GitHub
- 2026-05-18: advisory: CVE published and NVD record created

## References

- [https://github.com/EIPStackGroup/OpENer](https://github.com/EIPStackGroup/OpENer)
- [https://github.com/EIPStackGroup/OpENer/issues/558](https://github.com/EIPStackGroup/OpENer/issues/558)

## Related threats

- [OpENer out-of-bounds read in EtherNet/IP ForwardOpen parser](https://junglewise.ai/threats/cve-2026-75353-opener-v2-3-commit-76b95cf-contains-an-out-of-bounds-read-in-the)
- [OpENer out-of-bounds read in ForwardOpen connection-path parser](https://junglewise.ai/threats/cve-2026-75351-opener-v2-3-commit-76b95cf-contains-an-out-of-bounds-read-in-the)
- [EIPStackGroup OpENer buffer overflow in GetAttributeList](https://junglewise.ai/threats/cve-2026-75350-eipstackgroup-opener-v2-3-master-commit-76b95cf-contains-a-buffer)
- [EIPStackGroup OpENer expired pointer dereference in EtherNet/IP CPF](https://junglewise.ai/threats/cve-2026-75347-eipstackgroup-opener-v2-3-and-master-up-to-commit-76b95cf-contain)
- [EIPStackGroup OpENer out-of-bounds read in Connection Manager](https://junglewise.ai/threats/cve-2026-75349-eipstackgroup-opener-v2-3-0-master-up-to-commit-76b95cf-contains)