CVE-2026-51538

Published Jul 13, 2026 CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed
Description
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.

Analysis

AI-generated

Technical impact

The vulnerability is an incorrect access control flaw in EIPStackGroup OpENer 2.3.0. When the server processes critical encapsulation commands, it checks that the supplied session_handle exists in the global list but does not verify that the handle belongs to the TCP connection making the request. Because session handles are not tightly bound to originating sockets, an attacker can forge a request using a handle that belongs to another legitimate client and bypass the intended access controls, enabling unauthorized operation. This flaw corresponds to CWE‑284, which reflects an improper authorization check and can lead to privileged command execution if the server permits actions behind the protected encapsulation interface.

Affected Systems

EIPStackGroup OpENer version 2.3.0 is affected. Vendor and product names are EIPStackGroup and OpENer; the CVE data does not list additional vendor or product variants.

Risk and Exploitability

The CVSS score of 9.1 indicates a critical severity. EPSS < 1% suggests a low probability of exploitation in the wild, and the vulnerability is not presently listed in the CISA KEV catalog. The likely attack vector is a network-based attacker who can reach the OpENer service over TCP. An attacker only needs knowledge of a valid session handle created by an authenticated client and network connectivity to the service. With these conditions, the attacker can covertly issue encapsulation commands with the borrowed handle, effectively bypassing authorization and gaining unauthorized control over the device's encapsulation functionality.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the official vendor patch or upgrade to the latest OpENer release that implements strict session handle validation.
  • Restrict the OpENer service to trusted hosts by configuring firewall rules, VLAN segmentation, or VPN, ensuring that only authorized networks can establish connections.
  • Enable detailed logging of encapsulation command activity and monitor logs for repeated use of a single session_handle from different IP addresses or ports; set up alerts to detect potential access‑control bypass attempts.

Generated by OpenCVE AI on August 1, 2026 at 11:00 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Opener Project
Opener Project opener
CPEs cpe:2.3:a:opener_project:opener:2.3.0:*:*:*:*:*:*:*
Vendors & Products Opener Project
Opener Project opener
Type Values Removed Values Added
Title Session Handle Access Control Bypass in EIPStackGroup OpENer
Type Values Removed Values Added
Title Session Handle Access Control Bypass in EIPStackGroup OpENer
Type Values Removed Values Added
Title Insufficient Session Binding Enables Unauthorized Access in EIPStackGroup OpENer 2.3.0
Type Values Removed Values Added
Title Insufficient Session Binding Enables Unauthorized Access in EIPStackGroup OpENer 2.3.0
Type Values Removed Values Added
Weaknesses CWE-284
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Eipstackgroup
Eipstackgroup opener
Vendors & Products Eipstackgroup
Eipstackgroup opener
Type Values Removed Values Added
Description 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.
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Jul 14, 2026, 1:13 PM
Reserved
Jun 8, 2026, 12:00 AM
Status
Analyzed
Published
Jul 13, 2026, 10:16 PM
Modified
Aug 11, 2026, 4:38 PM