CVE-2026-67856 json
An issue in open62541 v.1.5.5 and before allows a remote attacker to cause a denial of service via crafted CreateSubscription, CreateMonito…
published 2026-08-04 3 mo ago modified 2026-08-31 2 mo ago also EUVD-2026-52968
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 55%
- public exploits
- 0
- none known
Summary
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
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-67856 updated cvss 7.5
open62541: open62541: Denial of Service via crafted subscription requests
-
Red Hat All currently supported Red Hat productsnot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 3 mo ago
Exploit prediction
0.76% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/open62541/open62541/issues/8092 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Classification
- Weakness
-
- CWE-400 Uncontrolled Resource Consumption
References
-
github.com
/open62541/open62541/issues/8092
exploit
- github.com /open62541/open62541/blob/master/src/server/ua_services_subscription.c
- github.com /open62541/open62541/blob/master/src/server/ua_subscription.c
- github.com /open62541/open62541/blob/master/src/server/ua_subscription.h
- github.com /open62541/open62541/blob/master/examples/access_control/server_access_control.c
Sources
- CVE List CVE-2026-67856
- NVD CVE-2026-67856
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.