Port 11371OpenPGP Keyserver
Port 11371 is primarily used by OpenPGP HTTP key servers, which facilitate the distribution, retrieval, and synchronization of public encryption keys. This enables a global infrastructure where users can upload or search for OpenPGP public keys to verify digital signatures, exchange secure messages, and support encrypted communication. These servers generally operate over HTTP, creating a public directory of keys to foster secure and trusted communications among users and services..
- transport
- unknown
- in transit
- cleartext
- assignment
- official
- risk
- 4/10
- lookups
- 22,463
single transport
payload readable on path
registered with iana
caution
rank 92 of 993 · top 9%
Technical Details
what runs on :11371OpenPGP HTTP key servers operate on port 11371 to provide access points where users can publish or retrieve PGP (Pretty Good Privacy) public keys. These servers underpin web-of-trust models and facilitate the decentralized verification of digital identities through the distribution of cryptographic keys.
The server typically employs the HTTP Keyserver Protocol (HKP), which allows clients to submit queries or upload keys via standard HTTP requests. This protocol is designed to be lightweight, interoperable, and broadly accessible, encouraging widespread adoption for secure communications. Since HKP requests run over HTTP by default (unencrypted), keys are transmitted in plaintext unless layered over TLS-enabled proxies or tunnels.
OpenPGP key servers also support key synchronization with other servers, helping to maintain a broadly distributed and redundant key directory infrastructure worldwide. This synchronization improves key availability and resilience, though it can make key revocation management challenging due to propagation delays.
Security Information
exposure of :11371risk 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
unknown
every listening transport is another surface to filter at the edge
security overview
Common Vulnerabilities:
- Since servers frequently run over unencrypted HTTP, transmitted key data can be vulnerable to eavesdropping and Man-in-the-Middle (MitM) attacks.
- The lack of authentication mechanisms means attackers may attempt key poisoning by uploading malicious or counterfeit keys associated with legitimate identities.
- Attackers can flood key servers with bogus keys, causing Denial of Service (DoS) or polluting the public key infrastructure.
Common Mitigations:
- Deploy TLS/HTTPS on top of port 11371 (using stunnel or reverse proxies) to protect data in transit and prevent interception.
- Implement rate limiting and upload validation policies to deter mass key poisoning and DoS attacks.
- Use client-side verification, including fingerprint confirmations and signature checks, rather than trusting servers alone, to mitigate risks of malicious key data.
- Routinely synchronize with trusted key servers to propagate revocations and clean the dataset.
Related Ports
the 8 most looked-up other ports in security — 216 ports carry that label.
| port | service | risk | |||
|---|---|---|---|---|---|
| :8881 | Atlasz Secure Server | TCP | Web Services | caution | 67.6k |
| :443 | HTTPS | TCPtls | Web Services | caution | 65.9k |
| :8291 | Winbox MikroTik Admin | TCP | Security | caution | 62.9k |
| :3268 | Microsoft Global Catalog (GC) | TCPUDP | Security | caution | 54.6k |
| :135 | Microsoft EPMAP | TCPUDP | Security | caution | 51.9k |
| :3128 | Squid Proxy HTTP | TCP | Web Services | caution | 45.8k |
| :8080 | HTTP Alternate | TCPtls | Web Services | caution | 44.9k |
| :7000 | Vuze HTTPS Tracker | TCPtls | Security | caution | 28.9k |
risk mix of the 8 listed
- caution100%
3 of 8 encrypted