CVE-2026-67856

Publication date 4 August 2026

Last updated 7 August 2026

Ubuntu priority

Cvss 3 Severity Score

Description

An issue in open62541 v.1.5.5 and before allows a remote attacker to cause a denial of service via crafted CreateSubscription, CreateMonitoredItems(Sampling), Publish, TransferSubscriptions, and DeleteSubscriptions requests

Status

Show unmaintained releases

Package	Ubuntu Release	Status
open62541	26.04 LTS resolute	Needs evaluation
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release

How can I get the fixes?
What do statuses mean?

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Base metrics

Parameter	Value
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality impact	None
Integrity impact	None
Availability impact	High

Scores

Parameter	Value
Base score	7.5 · High
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

MITRE
NVD
Launchpad
Debian

Other references

https://www.cve.org/CVERecord?id=CVE-2026-67856
https://github.com/open62541/open62541/issues/8092
https://github.com/open62541/open62541/blob/master/examples/access_control/server_access_control.c
https://github.com/open62541/open62541/blob/master/src/server/ua_services_subscription.c
https://github.com/open62541/open62541/blob/master/src/server/ua_subscription.c
https://github.com/open62541/open62541/blob/master/src/server/ua_subscription.h