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CVE-2026-67856: n/a

0
High
VulnerabilityCVE-2026-67856cvecve-2026-67856
Published: 08/04/2026 (08/04/2026, 00:00:00 UTC)
Source: CVE Database V5

Description

A denial of service vulnerability exists in open62541 version 1.5.5 and earlier. Remote attackers can exploit this issue by sending specially crafted OPC UA service requests such as CreateSubscription, CreateMonitoredItems (Sampling), Publish, TransferSubscriptions, and DeleteSubscriptions. This leads to resource exhaustion or application disruption without requiring authentication.

CVSS v3.1

Score 7.5high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected software

GitHub Actionsmore threats →ai
open62541/open62541
pkg:github/open62541/open62541
Affected versions
<=1.5.5

Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 08/12/2026, 15:12:52 UTC

Technical Analysis

CVE-2026-67856 is a denial of service vulnerability affecting open62541 versions up to and including 1.5.5. The flaw allows unauthenticated remote attackers to cause a denial of service by sending crafted OPC UA service requests related to subscription and monitored item management. The vulnerability is classified under CWE-400 (Uncontrolled Resource Consumption). No official patch or remediation guidance has been published at this time.

Potential Impact

Successful exploitation results in denial of service, causing the affected open62541 server or client to become unresponsive or crash. There is no impact on confidentiality or integrity, only availability is affected.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider limiting exposure of the OPC UA service to untrusted networks and monitoring for abnormal request patterns targeting subscription management services.

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Technical Details

Data Version
5.2
Assigner Short Name
mitre
Date Reserved
2026-07-30T00:00:00.000Z
State
PUBLISHED

Threat ID: 6a725cbabf8831d5398274d4

Added to database: 08/04/2026, 21:42:18 UTC

Last enriched: 08/12/2026, 15:12:52 UTC

Last updated: 09/17/2026, 22:01:37 UTC

Views: 58

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