PT-2026-54970 · Open62541 Project / O6 Automation Gmbh · Open62541

Lorenzo Cannella · Published 2026-07-02 · Updated 2026-07-02 · CVE-2026-11946

NVD

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

An unauthenticated remote attacker can exhaust server memory via the GetEndpoints Discovery Service in open62541. The endpointUrl field of GetEndpointsRequest is not validated for length. An attacker can declare an arbitrarily large string (up to ~4.09 GB via the UInt32 length field) delivered across intermediate chunks without ever sending the final chunk. The server buffers all chunks in RAM indefinitely until the SecureChannel times out. The attack is pre-session and bypasses all encryption configurations.

The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.

Fix

Allocation of Resources Without Limits

Weakness Enumeration

CWE-789

CWE-770

Related Identifiers

CVE-2026-11946

Affected Products

Open62541

References · 4

• https://github.com/open62541/open62541/pull/8142/changes/d253818d6c5e870e1db0e360b18138c8bdc809ae · Patch
• https://github.com/open62541/open62541/pull/8142 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-11946 · Security Note
• https://github.com/open62541/open62541 · Note