Viscosity version 1.11.4 is now available for macOS! This update focuses on improving the performance of VPN connections using a TAP (bridged) setup on macOS 15, and includes an updated version of OpenSSL, as well as many small bug fixes and enhancements.

Unfortunately the recent macOS 15.0.1 update restricted access to the APIs Viscosity needs to implement its Virtual Ethernet driver for TAP connections. Older versions of Viscosity will automatically fall back to its secondary driver (so TAP VPN connections continue to function), however the performance of this driver was limited. This update significantly improves the performance (both throughput and latency) of Viscosity's secondary driver. This means that for almost all users with TAP connections they should see full performance on macOS 15.0.1+.

We're still working on restoring Viscosity's Virtual Ethernet driver functionality on macOS 15.0.1+ and expect to have it fully available again in the future as well. If you still encounter any issues connecting a TAP connection, please ensure that the TAP Driver is set to “Automatic” under Settings->Advanced.

This update also includes significant behind-the-scenes improvements, as we continue to modernise Viscosity's code base. In particular, this update has performance improvements to VPN connection management, as well as general memory safety improvements.

Version 1.11.4 Mac Release Notes:

The 1.11.4 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.