A proxy designed to add TLS encryption to existing clients and servers


Stunnel 5.58

  -  2.74 MB  -  Open Source
  • Latest Version

    Stunnel 5.72

  • Operating System

    Windows 7 64 / Windows 8 64 / Windows 10 64

  • User Rating

    Click to vote
  • Author / Product

    Michal Trojnara / External Link

  • Filename


  • MD5 Checksum


Sometimes latest versions of the software can cause issues when installed on older devices or devices running an older version of the operating system.

Software makers usually fix these issues but it can take them some time. What you can do in the meantime is to download and install an older version of Stunnel 5.58.

For those interested in downloading the most recent release of Stunnel or reading our review, simply click here.

All old versions distributed on our website are completely virus-free and available for download at no cost.

We would love to hear from you

If you have any questions or ideas that you want to share with us - head over to our Contact page and let us know. We value your feedback!

  • Stunnel 5.58 Screenshots

    The images below have been resized. Click on them to view the screenshots in full size.

    Stunnel 5.58 Screenshot 1

What's new in this version:

Security bugfixes:
- The "redirect" option was fixed to properly handle unauthenticated requests
- Fixed a double free with OpenSSL older than 1.1.0
- OpenSSL DLLs updated to version 1.1.1j

New features:
- New 'protocolHeader' service-level option to insert custom 'connect' protocol negotiation headers. This feature can be used to impersonate other software (e.g. web browsers)
- 'protocolHost' can also be used to control the client SMTP protocol negotiation HELO/EHLO value
- Initial FIPS 3.0 support

- X.509v3 extensions required by modern versions of OpenSSL are added to generated self-signed test certificates
- Fixed a tiny memory leak in configuration file reload error handling
- Merged Debian 05-typos.patch
- Merged with minor changes Debian 06-hup-separate.patch
- Merged Debian 07-imap-capabilities.patch
- Merged Debian 08-addrconfig-workaround.patch
- Fixed tests on the WSL2 platform
- NSIS installer updated to version 3.06 to fix a multiuser installation bug on some platforms, including 64-bit XP
- Fixed engine initialization
- FIPS TLS feature is reported when a provider or container is available, and not when FIPS control API is available