CVE-2026-10703
Deferred Deferred - Pending Action
Use After Free in EIPStackGroup OpENer

Publication date: 2026-06-03

Last updated on: 2026-06-03

Assigner: VulDB

Description
A security vulnerability has been detected in EIPStackGroup OpENer up to 2.3.0. Affected is the function CreateMessageRouterRequestStructure of the file cipmessagerouter.c of the component SendRRData Handler. The manipulation leads to use after free. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. The project was informed of the problem early through an issue report but has not responded yet.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-06-03
Last Modified
2026-06-03
Generated
2026-06-24
AI Q&A
2026-06-03
EPSS Evaluated
2026-06-22
NVD
CVE-2026-10703
EUVD
EUVD-2026-34062
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
eipstackgroup opener to 2.3.0 (inc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-416 The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
CWE-119 The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability exists in the OpENer EtherNet/IP stack, specifically in the CreateMessageRouterRequestStructure function within the SendRRData Handler component. It is a use-after-free (or use-after-return) issue caused by improper management of a pointer's lifetime. A crafted EtherNet/IP explicit-message packet can trigger this vulnerability by causing the system to dereference a pointer to a payload that has already been deallocated. This happens because the payload pointer is stored as a raw pointer across multiple parsing layers without copying, leading to the pointer being used after the stack frame it references has been freed.

The root cause is the passing of a stack-backed receive buffer through encapsulation and Common Packet Format (CPF) parsing layers, where the CPF layer stores the payload pointer incorrectly. This leads to a crash or potential denial of service when the message router later tries to use this invalid pointer.

Impact Analysis

The primary impact of this vulnerability is that it can be remotely exploited to cause a denial of service (DoS) condition by crashing the affected system. Since the vulnerability involves use-after-free, it may also potentially be leveraged for other attacks, but the confirmed impact is denial of service.

Detection Guidance

This vulnerability can be detected by monitoring for crafted EtherNet/IP explicit-message packets that trigger the use-after-return issue in the CreateMessageRouterRequestStructure() function during TCP SendRRData handling.

Detection may involve capturing and analyzing network traffic for suspicious or malformed EtherNet/IP packets targeting the SendRRData handler.

Since the vulnerability causes a crash or denial of service, monitoring application logs or system logs for crashes related to OpENer or the cipmessagerouter.c component can also help identify exploitation attempts.

Specific commands are not provided in the resources, but typical approaches include using packet capture tools like tcpdump or Wireshark to filter EtherNet/IP traffic (usually TCP port 44818) and inspecting for unusual explicit message packets.

Mitigation Strategies

Immediate mitigation steps include restricting network access to the vulnerable OpENer service, especially blocking or filtering TCP port 44818 to prevent remote exploitation.

Monitoring and limiting incoming EtherNet/IP explicit-message packets can reduce the risk of exploitation.

Since the project has not yet responded with a patch, consider applying network-level protections such as firewalls or intrusion prevention systems to detect and block suspicious packets.

Additionally, running OpENer in a controlled environment with limited exposure and enabling any available fuzzing or testing capabilities may help identify and mitigate exploitation attempts.

Compliance Impact

The provided information does not specify any direct impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-10703. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart