CVE-2026-51537
EIPStackGroup OpENer 2.3.0 (commit 76b95cf) has an out-of-bounds read issue in Connection Manager handling of ForwardOpen requests when processing short malformed packets.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.48%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
EIPStackGroup OpENer 2.3.0 (commit 76b95cf) has an out-of-bounds read issue in Connection Manager handling of ForwardOpen requests when processing short malformed packets. An attacker can send a valid ENIP outer frame carrying a malformed CIP ForwardOpen/LargeForwardOpen request, causing the parser to continue reading fields even when request data is insufficient. This issue is remotely triggerable via network traffic and does not require authentication.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.48% probability · 40th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- opener project/opener
- Source
- cve@mitre.org
References
- https://gist.github.com/MrAlaskan/a5fb0fb7765c9df80d28220ed558f04eThird Party Advisory
- https://github.com/EIPStackGroup/OpENer/issues/564Exploit, Issue Tracking, Vendor Advisory
- https://github.com/EIPStackGroup/OpENer/issues/564Exploit, Issue Tracking, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.