Short answer: Ghostunnel is an open-source tool that helps secure communication between applications using TLS. Use it to add mutual authentication to services that need it, without changing the application code.
TL;DR
- Ghostunnel acts as a TLS proxy.
- It works in server and client modes.
- Mutual authentication is ensured through certificates.
- It can be configured to use various certificate sources.
What happened?
Ghostunnel is an open-source tool that establishes secure communication between applications using TLS. It works in two modes: server and client. In server mode, it sits in front of a backend service, checking client certificates and passing traffic. In client mode, it does the reverse, adding TLS to local connections. Certificates can come from various sources, and the tool can be configured to reload them without restarting. Ghostunnel is designed to help applications that cannot handle TLS themselves by handling mutual authentication and secure communication.
Key facts
| Reported by | Help Net Security |
|---|---|
| Date reported | 04 Nov 2026 |
How it works
Ghostunnel is an open-source tool that acts as a TLS proxy. It works in two ways. In server mode, it sits in front of a backend service, checks client certificates, and forwards traffic. In client mode, it listens for local connections, wraps them in TLS, and presents a client certificate. This ensures mutual authentication between both sides.
- Sits in front of backend
- Checks client certificate
- Wraps local connections
- Presents client certificate
Timeline
| Date | Event | Source |
|---|---|---|
| 2026-11-04 | Reported by Help Net Security | Help Net Security |
| 2026-11-08 | This Skillmate explainer published | Skillmate |
How to fix it
- Keep systems and network devices updated and follow vendor security notices.
- Make sure an incident response contact and plan exist before an attack happens.
- Ask your service providers which protections they offer, and test them.
What is confirmed
- Reported by Help Net Security
Why it matters
Ghostunnel helps secure communication by ensuring mutual authentication. This is crucial for protecting sensitive data and maintaining trust between services. Companies and users benefit from its reliability and ease of use, especially when integrating with existing systems.
Learn the skills behind this story
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FAQ
What is mutual authentication?
Mutual authentication means both the client and server verify each other’s identity before establishing a secure connection.
Where can I get Ghostunnel?
Ghostunnel is available for free on GitHub.
How does Ghostunnel work?
In server mode, Ghostunnel accepts TLS connections, checks the client’s certificate, then passes traffic to the backend. In client mode, it listens for plain connections, wraps them in TLS, and presents a client certificate.
Sources
- Ghostunnel: Open-source TLS proxy with mutual authentication (Help Net Security)
How we wrote this: facts come from the sources above. An on-prem AI model drafted the plain-English parts and every sentence was checked against the sources; unsupported sentences were removed. MITRE mapping is our own judgement.