Port 4840OPC UA TCP
OPC Unified Architecture (OPC UA) is a machine-to-machine communication protocol for industrial automation developed by the OPC Foundation. It is designed to facilitate the secure and reliable exchange of data in industrial control systems, supporting complex data modeling while remaining platform-independent..
- transport
- tcp · udp
- in transit
- cleartext
- assignment
- official
- risk
- 4/10
- lookups
- 26,568
2 transports registered
payload readable on path
registered with iana
caution
rank 59 of 993 · top 6%
Technical Details
what runs on :4840OPC Unified Architecture (OPC UA) is an industry-standard communication protocol that enables secure, platform-independent exchange of industrial data. It serves as a successor to older OPC specifications, combining their functionalities and adding cross-platform and security enhancements. OPC UA abstracts hardware interfaces and provides a unified, object-oriented data model supporting complex system requirements.
Communication is primarily handled over TCP for reliable data transfer. Port 4840 is the default TCP port utilized for establishing OPC UA binary TCP connections, enabling efficient transmission of data. OPC UA supports additional transport mappings including Web Services bindings; however, TCP binary is commonly preferred due to performance benefits in real-time industrial contexts.
Designed for scalability, OPC UA can operate on embedded devices, factory floor PCs, and cloud environments. It enables not just data acquisition but also command/control interactions within SCADA, MES, and IoT systems. Its information modeling capabilities allow for rich semantic data representation that facilitates interoperability across multi-vendor industrial solutions.
Security Information
exposure of :4840risk score
4/ 10caution
worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.
network services averages 3.9 across 604 ports — this one sits 0.1 above.
in transit
cleartext
credentials and payloads are readable by anyone on path
assignment
official
registered with iana for this service — scanners fingerprint it by number
reachable over
tcp · udp
udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite
security overview
Common Vulnerabilities:
- Improper authentication or lack of security configurations can expose the server to unauthorized access.
- Implementation flaws may lead to buffer overflows or denial-of-service conditions.
- If security policies are disabled or improperly configured, data interception and man-in-the-middle attacks may occur.
- Legacy systems may not implement the latest OPC UA security features, creating attack surfaces.
Common Mitigations:
- Always enable and enforce strong authentication and authorization policies.
- Utilize built-in OPC UA encryption and signing to ensure data confidentiality and integrity.
- Keep OPC UA server and client implementations updated to address known bugs and vulnerabilities.
- Employ network segmentation and strict firewall rules, limiting access to trusted hosts.
- Conduct regular security assessments and disable unnecessary services or endpoints on the OPC UA servers.
Related Ports
the 8 most looked-up other ports in network services — 604 ports carry that label.
| port | service | risk | |||
|---|---|---|---|---|---|
| :9080 | Groove RPC | TCPUDP | Web Services | caution | 70.8k |
| :6543 | Jetnet | UDP | Network Services | caution | 65.3k |
| :5938 | TeamViewer | TCPUDP | Remote Access | caution | 65.0k |
| :8291 | Winbox MikroTik Admin | TCP | Security | caution | 62.9k |
| :3233 | WhiskerControl Protocol | TCPUDP | Network Services | caution | 61.9k |
| :3268 | Microsoft Global Catalog (GC) | TCPUDP | Security | caution | 54.6k |
| :135 | Microsoft EPMAP | TCPUDP | Security | caution | 51.9k |
| :3128 | Tatsoft Default HTTP Proxy | TCP | Web Services | caution | 46.8k |
risk mix of the 8 listed
- caution100%
0 of 8 encrypted