Medium severity · published Aug 4, 2026
CVE-2026-18784
o6 open62541 ua_client_highlevel.c UA_Client_readNodeClassAttribute heap-based overflow
5.3
CVSS
0.2%
EPSS
No
On KEV
Description
A vulnerability was found in o6 open62541 up to 1.5.5. This issue affects the function UA_Client_readNodeClassAttribute of the file src/client/ua_client_highlevel.c. Performing a manipulation results in heap-based buffer overflow. Attacking locally is a requirement. The exploit has been made public and could be used. The project closed the issue report, stating that this is not the official way to report a security vulnerability.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
open62541 · o6
1.5.0; 1.5.1; 1.5.2; 1.5.3; 1.5.4; 1.5.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-18784
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-18784
github.com
https://github.com/gff-cw/information/issues/11
github.com
https://github.com/open62541/open62541/issues/8139
vuldb.com
https://vuldb.com/cve/CVE-2026-18784
vuldb.com
https://vuldb.com/submit/857012
vuldb.com
https://vuldb.com/vuln/385786
vuldb.com
https://vuldb.com/vuln/385786/cti
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