CVE-2026-67856

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.42% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 34.4% of scored records. A rank, not a probability.

NVD base score

7.5 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Deferred. NVD last modified this record on 2026-08-31.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-08-04 00:00Z1 MO AGO

Last updated

2026-08-05 18:50Z1 MO AGO

Reserved

2026-07-30

Assigning CNA

mitre

Record state

PUBLISHED

Severity

High (CVSS 7.5)

CNA CVSS vector

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

Weaknesses

• CWE-400Uncontrolled Resource ConsumptionClass

Data version

5.2

Document digest

4611834420875ec5e7fc33f8ae79ffef403062f57e1755915a9a920814bc16d4

• github.comhttps://github.com/open62541/open62541/issues/8092
• github.comhttps://github.com/open62541/open62541/blob/master/src/server/ua_services_subscription.c
• github.comhttps://github.com/open62541/open62541/blob/master/src/server/ua_subscription.c
• github.comhttps://github.com/open62541/open62541/blob/master/src/server/ua_subscription.h
• github.comhttps://github.com/open62541/open62541/blob/master/examples/access_control/server_access_control.c