SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-51538

EIPStackGroup OpENer 2.3.0 (commit 76b95cf) suffers from an Incorrect Access Control vulnerability in its handling of encapsulation sessions.

CRITICAL 9.1EPSS 0.39%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.39%). 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) 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.

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS
0.39% probability · 32th percentile
CISA KEV
Not listed
Weakness
CWE-284
Affected
opener project/opener
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.