High severity · published Oct 24, 2026
CVE-2026-116014
open62541 1.5.0 before 1.5.7 Integer Overflow Heap Buffer Overflow via Custom DataType
New
8.1
CVSS
0.4%
EPSS
No
On KEV
Description
open62541 1.5.0 before 1.5.7 contains an integer overflow in UA_DataType_fromStructureDescription() that wraps the 16-bit memSize field for large custom structure definitions. A malicious OPC UA server can supply DataType definitions via UA_Client_getRemoteDataTypes(), causing decodeBinaryStructure() to overflow the heap, crashing clients or enabling code execution.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 37% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
open62541 · open62541
1.5.0 before 1.5.7 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-116014
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-116014
github.com
https://github.com/open62541/open62541/blob/v1.5.6/src/ua_types_definition.c#L274
github.com
https://github.com/open62541/open62541/commit/0cf4806768c493bc6ccffcd4419da24153b970ec
github.com
https://github.com/open62541/open62541/pull/8298
github.com
https://github.com/open62541/open62541/pull/8302
github.com
https://github.com/open62541/open62541/releases/tag/v1.5.7
www.vulncheck.com
https://www.vulncheck.com/advisories/open62541-1.5.0-before-1.5.7-integer-overflow-heap-buffer-overflow-via-custom-datatype
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