CVE-2026-51536
In OpENer 2.3.0 (commit 76b95cf) when parsing incoming CIP (Common Industrial Protocol) network packets, the length parameter is inconsistently typed across the call stack. Specifically, an upstream length calculated as an int is passed to a downstream function that expects an EipInt16 (a 16-bit signed integer). If a maliciously crafted packet with specific length fields is processed, the length parameter can overflow or be truncated into a negative value. This negative length bypasses subsequent bounds checking (due to signed/unsigned comparison issues) and is ultimately used in memory operations, leading to a Stack Buffer Overflow when reading data in DecodePaddedEPath.
Published:Jul 13, 2026
Last Modified:Aug 11, 2026
EPS:Jul 13, 2026
EPSS Score:0.00472
CVSS Score:9.1
Affected Products
Vendor
Product
Action
Vendor
Eipstackgroup
Product
Opener
Eipstackgroup
Opener
Vendor
Opener Project
Product
Opener
Opener Project
Opener
Exploits
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
