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: OpENer: Out-of-bounds read via malformed ForwardOpen requests

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.

EIPStackGroup OpENer 2.3.0 (commit 76b95cf) suffers from an Incorrect Access Control vulnerability in its handling of encapsulation sessions. When the server processes critical encapsulation commands, it verifies whether the provided session_handle exists in the global session list, but it fails to verify whether that handle belongs to the specific TCP connection issuing the request. Because there is no strong binding between a session handle and its originating socket, any attacker on the network can use a valid session handle created by another legitimate client to bypass access controls.

Memory Corruption via Integer Underflow in OpENer SendUnitData

OpENer 2.3.0 (master branch up to commit 76b95cf) is vulnerable to a severe memory corruption issue caused by an integer underflow in the processing of connected explicit messages (SendUnitData).

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 path_size field claims that many more path words are present than are actually available. Because the parser trusts the attacker-controlled path_size and continues decoding path segments without a remaining-length boundary, it reads beyond the end of the stack receive buffer.

An out-of-bounds write vulnerability exists in the GetAttributeList attribute_count_request functionality of EIP Stack Group OpENer development commit 58ee13c. A specially crafted EtherNet/IP request can lead to an out-of-bounds write, potentially causing the server to crash or allow for remote code execution. An attacker can send a series of EtherNet/IP requests to trigger this vulnerability.

EIPStackGroup OpENer Ethernet/IP Incorrect Conversion between Numeric Types

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may cause a denial-of-service condition.

EIPStackGroup OpENer Ethernet/IP Out-of-bounds Read

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may allow the attacker to read arbitrary data.

EIPStackGroup OpENer Ethernet/IP Reachable Assertion

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may result in a denial-of-service condition.

EIPStackGroup OpENer Ethernet/IP Reachable Assertion

A specifically crafted packet sent by an attacker to EIPStackGroup OpENer EtherNet/IP commits and versions prior to Feb 10, 2021 may result in a denial-of-service condition.

A use-of-uninitialized-pointer vulnerability exists in the Forward Open connection_management_entry functionality of EIP Stack Group OpENer development commit 58ee13c. A specially-crafted EtherNet/IP request can lead to use of a null pointer, causing the server to crash. An attacker can send a series of EtherNet/IP requests to trigger this vulnerability.

An out-of-bounds write vulnerability exists in the SetAttributeList attribute_count_request functionality of EIP Stack Group OpENer development commit 58ee13c. A specially crafted EtherNet/IP request can lead to an out of bounds write, potentially causing the server to crash or allow for remote code execution. An attacker can send a series of EtherNet/IP requests to trigger this vulnerability.

EIPStackGroup OpENer v2.3.0 was discovered to contain a stack overflow via /bin/posix/src/ports/POSIX/OpENer+0x56073d.

An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer 2.3 and development commit 8c73bf3. A specially crafted network request can lead to an out-of-bounds read.

An out-of-bounds write vulnerability exists in the Ethernet/IP server functionality of EIP Stack Group OpENer 2.3 and development commit 8c73bf3. A specially crafted series of network requests can lead to remote code execution. An attacker can send a sequence of requests to trigger this vulnerability.

A denial-of-service vulnerability exists in the Ethernet/IP server functionality of the EIP Stack Group OpENer 2.3 and development commit 8c73bf3. A large number of network requests in a small span of time can cause the running program to stop. An attacker can send a sequence of requests to trigger this vulnerability.