OpENer 2.3.0 (commit 76b95cf) has an out-of-bounds read issue in CIP message parsing when handling malformed explicit requests with a forged EPath size. An attacker can send a valid ENIP SendRRData frame carrying a very short CIP payload whose pathsize field claims that many more path words are present than are actually available. Because the parser trusts the attacker-controlled pathsize and continues decoding path segments without a remaining-length boundary, it reads beyond the end of the stack receive buffer.

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.

OpENer v2.3.0 / commit 76b95cf contains an out-of-bounds read in the unconnected explicit messaging path. This allows a remote attacker to cause a denial of service.

OpENer v2.3/commit 76b95cf, contains an out-of-bounds read in the server-side EtherNet/IP ForwardOpen connection-path parser. This allows a remote attacker to cause a denial of service.

OpENer v2.3-558-g1e99582 contains an out-of-bounds read vulnerability in the Common Packet Format (CPF) parser, specifically in CreateCommonPacketFormatStructure() in source/src/enetencap/cpf.c. A crafted ENIP/CPF message can supply an attacker-controlled itemcount value that is not consistently validated against the remaining datalength of the CPF slice

OpENer v2.3/ commit 76b95cf, contains an out-of-bounds read in the server-side EtherNet/IP ForwardOpen connection-path parser. This allows a remtoe attacker to cause a denial of service

OpENer v2.3/commit 76b95cf, contains an integer underflow in the server-side EtherNet/IP ForwardOpen connection-path parser. This allows a remote attacker to cause a denial of service