CVE-2026-116014
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 4.0
- 9.2 CRITICALCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.43% probability · 37th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-190
- Source
- disclosure@vulncheck.com
EPSS moved from 0.4% on 25 October 2026 to 0.4% on 26 October 2026.
References
- https://github.com/open62541/open62541/blob/v1.5.6/src/ua_types_definition.c#L274
- https://github.com/open62541/open62541/commit/0cf4806768c493bc6ccffcd4419da24153b970ec
- https://github.com/open62541/open62541/pull/8298
- https://github.com/open62541/open62541/pull/8302
- https://github.com/open62541/open62541/releases/tag/v1.5.7
- https://www.vulncheck.com/advisories/open62541-1.5.0-before-1.5.7-integer-overflow-heap-buffer-overflow-via-custom-datatype
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.