Is CVE-2026-33592 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-33592 being exploited in the wild.

How severe is CVE-2026-33592?

High severity, with a CVSS score of 7.5, published 2 July 2026.

Which products and versions are affected?

Open62541 Project Open62541 1.4.0 through 1.4.16, 1.5.0 through 1.5.4, master.

Is there a fix for CVE-2026-33592?

A patch was published on 2026-06-23: Fix merged into 1.4 branch via Pull Request 8142 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-33592 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-33592?

Check whether you run Open62541 Project Open62541 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-33592: open62541 memory exhaustion in FindServers Discovery Service

CVE-2026-33592 · Severity: high · CVSS 7.5 · Published 2026-07-02

A vulnerability in the open62541 library, an open-source implementation of the OPC UA industrial communication standard, allows an attacker to crash or disable a server. By sending specially crafted requests that lack size limits, an attacker can force the server to consume all available memory. This can lead to a total service outage, disrupting industrial operations and monitoring without requiring any user credentials.

Technologies: Open62541 Project Open62541. Vendors: Open62541 Project.

Quick answers

Is CVE-2026-33592 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-33592 being exploited in the wild.
How severe is CVE-2026-33592?: High severity, with a CVSS score of 7.5, published 2 July 2026.
Which products and versions are affected?: Open62541 Project Open62541 1.4.0 through 1.4.16, 1.5.0 through 1.5.4, master.
Is there a fix for CVE-2026-33592?: A patch was published on 2026-06-23: Fix merged into 1.4 branch via Pull Request 8142 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-33592 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-33592?: Check whether you run Open62541 Project Open62541 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A denial-of-service vulnerability exists in open62541 due to improper validation of the 'serverUris' field within a 'FindServersRequest'. An unauthenticated remote attacker can initiate a pre-session request and declare an arbitrarily large string (up to ~3.9 GB) delivered across multiple intermediate chunks. Because the server does not validate the array size or string length and buffers all chunks in RAM until the SecureChannel times out, an attacker can exhaust available system memory. This bypasses encryption configurations as it occurs before session establishment. The issue has been addressed by enforcing default message and chunk size limits (e.g., 512 MB per message and 16384 chunks) when configurations are set to zero.

Affected products

open62541 project / o6 Automation GmbH open62541 1.4.0 through 1.4.16, 1.5.0 through 1.5.4, master

Timeline

2026-06-23: patched: Fix merged into 1.4 branch via Pull Request 8142
2026-07-02: disclosed: CVE published to NVD

References

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