CVE-2026-11946
An unauthenticated remote attacker can exhaust server memory via the GetEndpoints Discovery Service in open62541. The endpointUrl field of GetEndpointsRequest is not validated for length. An attacker can declare an arbitrarily large string (up to ~4.09 GB via the UInt32 length field) delivered across intermediate chunks without ever sending the final chunk. The server buffers all chunks in RAM indefinitely until the SecureChannel times out. The attack is pre-session and bypasses all encryption configurations. The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.
Published:Jul 2, 2026
Last Modified:Jul 6, 2026
EPS:Jul 2, 2026
EPSS Score:0.00386
CVSS Score:7.5
Affected Products
Vendor
Product
Action
Vendor
Open62541
Product
Open62541
Open62541
Open62541
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
