Unauthenticated crash via incorrect connection-path length accounting
Published Oct 9, 2026 · Updated Oct 9, 2026
Out-of-bounds reads in OpENer 2.3 ForwardOpen parsing allow remote attackers to crash the server via crafted EtherNet/IP requests. ParseConnectionPath decrements the remaining path length using decoded values rather than encoded segment widths, allowing reads beyond the receive buffer. The default sample server is reachable without authentication after EtherNet/IP session registration; the demonstrated consequence is a crash, not code execution.
Summary
What happened
Out-of-bounds reads in OpENer 2.3 ForwardOpen parsing allow remote attackers to crash the server via crafted EtherNet/IP requests. ParseConnectionPath decrements the remaining path length using decoded values rather than encoded segment widths, allowing reads beyond the receive buffer. The default sample server is reachable without authentication after EtherNet/IP session registration; the demonstrated consequence is a crash, not code execution.
The record
- CVE
- CVE-2026-75351
- Published
- Oct 9, 2026
- Updated
- Oct 9, 2026
- Vendor
- EIPStackGroup
- Product
- OpENer
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 9, 2026CVE publishedPublication date reported by the CVE source.
- Oct 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=n/a
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
- ForwardOpen connection-path crash reproductionproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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