Port 3516Smartcard Service
Port 3516 is primarily used for smartcard communication services, allowing secure interactions between smartcard readers and authentication systems. It acts as a transport layer facilitating the exchange of authentication, identification, and cryptographic information during smartcard transactions across various enterprise and networked environments..
- transport
- tcp · udp
- in transit
- cleartext
- assignment
- official
- risk
- 4/10
- lookups
- 7,971
2 transports registered
payload readable on path
registered with iana
caution
rank 640 of 993 · top 64%
Technical Details
what runs on :3516Port 3516 serves as a communication endpoint for smartcard-related services, typically handling data exchanges between smartcard readers and host machines. Its primary function revolves around user identification, secure login processes, and secure transactions facilitated via smartcards in enterprise systems, banking, and personal identification scenarios.
Communication over this port often involves the transfer of sensitive authentication credentials, cryptographic keys, or user data encoded or signed by the smartcard hardware. The protocol stack used may involve proprietary or standardized messaging protocols designed to interact with smartcard chipsets, middleware, and authentication services.
Support for both TCP and UDP on this port allows for flexible deployment models; TCP is used for reliable, connection-oriented sessions, while UDP might be employed for lightweight status checks or discovery mechanisms. Though not officially encrypted by default, smartcard protocols typically embed cryptographic protections within data payloads for integrity and confidentiality.
Security Information
exposure of :3516risk score
4/ 10caution
worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.
security averages 3.8 across 216 ports — this one sits 0.2 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:
- Man-in-the-middle attacks if session encryption is not correctly implemented.
- Replay attacks where intercepted authentication data is reused.
- Exploitation of software vulnerabilities in smartcard middleware or drivers causing privilege escalation or unauthorized access.
- Potential exposure of sensitive authentication data if transmitted in plaintext.
Common Mitigations:
- Enforce end-to-end encryption, such as TLS, on smartcard communication sessions.
- Implement mutual authentication protocols to avoid impersonation.
- Regularly update smartcard middleware and firmware to patch vulnerabilities.
- Apply strong access control, network segmentation, and monitoring to detect suspicious activities targeting port 3516.
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risk mix of the 8 listed
- caution100%
3 of 8 encrypted