Viscosity 1.9 is now available for both macOS and Windows! This is one of our biggest updates yet, with significant changes under-the-hood and many new features.

One of the most anticipated additions in version 1.9 is support for macOS 11 (Big Sur). Viscosity now supports and integrates with macOS 11, and all of Viscosity's existing functionality is fully supported (including TAP support - more on that below).

We've also ported Viscosity to have complete native support for the upcoming Apple Silicon (ARM) Macs. Viscosity and your VPN connections will run at native speed to take full advantage of the new processor architecture and power savings.

Version 1.9 also introduces driverless TAP (bridged) connection support on macOS. This is something we are particularly enthusiastic about: if you use TAP (bridged) OpenVPN connections you'll no longer need to manually approve a kernel extension to load before you're able to connect. This will also make deployment much easier in enterprise environments. And best of all, our approach fully supports macOS 11.

On the Windows side, version 1.9 introduces a brand-new VPN network adapter driver for Windows 10 2004 and later. This driver has been written from the ground up for modern Windows 10 machines. It does away with using legacy system frameworks to help optimise performance and lower resource usage. It also includes privacy improvements, such as generating a random ethernet (MAC) address each time you connect, as well as better support for custom MTU values and custom MAC addresses (using the lladdr command) for TAP connections.

A common request from Viscosity power users is for more powerful scripting support, and we're pleased to be able to say we've done just that. Both AppleScript scripts on macOS, and Batch scripts on Windows now have access to connection details, making it easier to write scripts that respond to different network changes. This also makes it easier to share scripts between connections, or even different users.

It's now also possible for Before-Connect scripts to return username and password credentials, making it easy to craft custom authentication prompts, integrate with custom authentication systems, or manually handle credential storage.

The Windows version also updates the DNS system to improve the reliability of Network Location Awareness (NLA) when connected to a VPN on newer versions of Windows 10. This should resolve an issue where certain applications, such as Microsoft Office, may be unable to use network services while connected. Also addressed in the Windows update is a low-severity security vulnerability that could allow certain libraries to be side-loaded from the same directory when the Windows installer is run. Thank you to Vladimir Dubrovin for reporting this.

It's also important to note that this update drops support for OpenVPN 2.3. Viscosity will still be able to connect to servers running OpenVPN 2.3 or older versions, however OpenVPN 2.4 will now be used client-side. For the vast majority of users no migration changes are needed and connections will automatically work. However if you've updated and can no longer connect please refer to our migration guide.

Finally, version 1.9 also includes many more small improvements and bug fixes. For further information please refer to the release notes below.

Version 1.9 Mac Release Notes:

Version 1.9 Windows Release Notes:

The 1.9 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.8.6 is now available for both macOS and Windows! This update brings a number of small improvements, updated OpenVPN and OpenSSL versions, two-factor authentication enhancements, and small bug fixes.

In particular, on the macOS side U2F support has been overhauled to offer a smoother device registration process as well as support for additional devices. It also lays the groundwork for FIDO2 support in a future update to Viscosity.

The Windows version has also overhauled remote server endpoint selection to match the Mac version's functionality. In particular, the Windows version now also supports round-robin DNS for server domains that resolve to multiple IP addresses. Reachability checking at the start of a connection has also been improved, with local reachability problems detected sooner.

The macOS version also resolves two issues that could result in a connection appearing stuck in a "Disconnecting" state after waking the computer from sleep. This was caused by rapid Power Nap or Wake-on-LAN events causing the computer to wake for very short periods of time. Viscosity should now handle these short wake events correctly.

Finally, this version also updates OpenVPN to version 2.4.9, and OpenSSL to version 1.1.1g, for both platforms.

Version 1.8.6 Mac Release Notes:

Version 1.8.6 Windows Release Notes:

The 1.8.6 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.8.5 is now available for both macOS and Windows! This update is primarily a maintenance release to keep Viscosity and your VPN connections running smoothly.

In light of the COVID-19 pandemic, we've limited this update to bug fixes and small improvements only, with no major changes. We've received countless reports of Viscosity playing a widespread and vital role for businesses and educational institutions with staff working from home. In such an environment the last thing we want is for changes to Viscosity's behaviour or user interface to surprise users or add additional workload to already overburdened staff.

On the macOS side, this update resolves a number of rare crashes that have been reported to us, as well as an issue that could prevent custom menu item scripts in a bundled version of Viscosity from running. An issue where Full DNS wouldn't be applied when using a split-routed TAP/bridged connection using DHCP for IP assignment has also been resolved.

The Windows version has a number of small improvements to both the DNS and networking to improve reliability, especially in certain enterprise setups. In particular, Viscosity is now better able to prevent loopback DNS settings remaining in rare situations caused by a Windows crash or surprise hardware removal. An issue where users may not get prompted for their U2F credentials on some Windows 10 machines has been resolved, as well as an issue that could cause VPN connections to fail to automatically reconnect.

We’re also aware of difficulty using the SafeNet Authentication Client (SAC) PKCS#11 driver with Viscosity 1.8.4 and earlier on macOS 10.15. The driver does not conform to macOS 10.15's dynamic library linking requirements, and so macOS blocks it from loading. We've been informed that updating to the latest version of the driver (10.2 Post GA R2) should resolve this. For those stuck on older versions of the driver, we've also managed to implement a workaround in Viscosity to allow the driver to load.

We've also received reports of two enterprise security software packages, namely "SentinelOne" and "Digital Guardian", causing Viscosity to crash under macOS 10.15. Users have reported crashes when attempting to launch Viscosity, when attempting to connect a VPN connection, or when clicking on a password field. The fault lies with these software packages being incompatible with macOS 10.15's "hardened runtime" requirement. The developers of both software packages have reported this has been fixed in their respective latest versions. If you are using a workplace-supplied device and are experiencing these crashes, please ask your IT staff to update the relevant software to the latest version.

Users with TAP connections upgrading to macOS 10.15.4 may also receive a "Legacy System Extension" warning from macOS, indicating that future versions of macOS may no longer support the TAP driver. Rest assured that we have already been working on a solution for the next major version of macOS.

Finally, this update also updates OpenSSL to version 1.1.1f for both platforms.

Version 1.8.5 Mac Release Notes:

Version 1.8.5 Windows Release Notes:

The 1.8.5 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.8.4 is now available for both macOS and Windows! This update includes two-factor token authentication improvements, an updated version of OpenSSL for OpenVPN 2.3, a low-severity security fix, and a number of small bug fixes and improvements for both platforms.

On the authentication side, a number of PKCS#11 issues have been addressed on both platforms, which should allow additional tokens and certificate/keys to be used for authentication. This should also resolve certain keys not working in the previous two releases of Viscosity.

Viscosity now also supports importing connections that include an inline username and password. These will automatically be loaded into the Keychain or Windows Credential Manager at import time for safe storage.

On the Mac Viscosity will now automatically detect when the "Disable Time Machine backups while connected" feature is blocked. macOS 10.15 requires that applications be granted the "Full Disk Access" privilege to enable or disable automatic backups. If granted, Viscosity will only use this privilege to enable/disable Time Machine backups, and only if the feature is enabled.

This update also contains two security related updates. Firstly, OpenVPN 2.3 is now updated to use OpenSSL 1.0.2u (OpenVPN 2.4 will continue to use OpenSSL 1.1.1d). With OpenSSL 1.0.2 now end of life, Viscosity will likely be dropping OpenVPN 2.3 later in the year (please keep in mind that OpenVPN 2.4 is backwards compatible with servers running older versions of OpenVPN).

Secondly, this update also addresses a low-severity security vulnerability (CVE-2020-5180). An attacker with local access could potentially run arbitrary code within Viscosity's OpenVPN sandbox by using a maliciously crafted OpenSSL engine and associated command. Such an attack is successfully contained within Viscosity's sandbox, which has de-elevated permissions and access restrictions, and so an attacker does not gain elevated local permissions (such as root or SYSTEM) on the machine and their actions are severely limited.

However, under macOS an attacker may be able to access on-disk VPN credentials (such as a certificate and private key) from other active OpenVPN connections that run within the sandbox at the same time. This does not apply to the Windows version. Because of this, we encourage those in multi-user macOS environments to update as soon as possible. Special thanks to Rich Mirch for identifying and reporting this issue.

Version 1.8.4 Mac Release Notes:

Version 1.8.4 Windows Release Notes:

The 1.8.4 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.8.3 is now available for both macOS and Windows! This update is primarily a small maintenance release with bug fixes and minor enhancements.

Most notably, Viscosity will now prompt to allow connections to OpenVPN setups with certificates where a weak CA digest is detected. This should make it easier to connect to legacy servers without the need to manually adjust any advanced commands.

The Mac update also addresses a regression that could cause EC keys on PKCS#11 devices to be unusable, as well as some small fixes when running on older versions of macOS.

Version 1.8.3 Mac Release Notes:

Version 1.8.3 Windows Release Notes:

The 1.8.3 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Version 1.8.2 of Viscosity has been released for both macOS and Windows! This update includes both updated versions of OpenVPN (2.4.8) and OpenSSL (1.1.1d), as well as many improvements and bug fixes for both platforms.

In particular, with the update to the OpenSSL 1.1.1 branch we've been able to enable support for TLS version 1.3 and the latest ciphers in Viscosity. When connecting to up to date OpenVPN servers this will allow for more secure and performant VPN connections.

The Windows version of Viscosity has also been overhauled to allow it to run on devices using ARM processors (WoA64 support). Along with supporting ARM, we've been able to include a small additional performance boost to VPN connections.

On the Mac side, this version should feel snappier when running on macOS Catalina, as we've been able to adopt some of the new macOS frameworks. The Mac version also includes some small additional improvements, including faster handling when there are multiple VPN connections connected simultaneously, and additional AppleScript controllability.

Version 1.8.2 Mac Release Notes:

Version 1.8.2 Windows Release Notes:

The 1.8.2 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.8.1 is now available for both macOS and Windows! This update is primarily a maintenance release and it includes a number of small tweaks and improvements for both platforms.

Viscosity now integrates the new U2F APIs introduced in Windows 10 1903. This provides a more native and consistent experience for users also using U2F for Windows authentication, as well as resolving U2F access issues under Windows 10 1903.

We've also worked behind the scenes to make deploying Viscosity in managed macOS environments much easier. Deployments in multi-user environments has been simplified, and the managed installer templates are now able to handle the Start on Login option without the need for custom scripts. Documentation is also now available on how to deploy Viscosity using tools like Munki and Jamf.

Finally, we've also identified some OpenVPN server setups that will unnecessarily push a route-delay command, significantly delaying connection time. Viscosity will now ignore this command when it isn't needed.

Version 1.8.1 Mac Release Notes:

Version 1.8.1 Windows Release Notes:

The 1.8.1 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity 1.8 is now available for both macOS and Windows! This is a big update, with significant performance improvements for VPN connections. Both macOS and Windows users should immediately notice their OpenVPN connections connecting faster, with slightly lowered CPU usage. Windows users should also notice significantly improved maximum throughput on high-speed network connections.

A traffic graph has also been added to the main menu, providing a quick overview of how your VPN connection is being utilised without needing to open the Details menu. The style of this graph can also be customised from the Appearance section, or turned off for those who prefer to keep things simple.

By popular demand we've also overhauled Viscosity's menu icon system. Not only has this allowed us to include some snappy new icon designs to choose from, all icons now feel much more at home on both macOS and Windows. In particular, on macOS icons with coloured components will now look great in both light and dark mode, behave correctly when selected, and on secondary monitors as well.

On Windows Viscosity now also supports Network Location Awareness for routed/TUN connections. This will resolve an issue that caused some applications, including Microsoft Office and many UWP based apps, from failing to detect that a network connection is available when a VPN connection is connected.

Finally, version 1.8 also brings offical support for macOS 10.15 (Catalina), which is expected to be released next month.

Version 1.8 Mac Release Notes:

Version 1.8 Windows Release Notes:

The 1.8 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.7.16 is now available for both macOS and Windows! This update is primarily a small maintenance release with a focus on bug fixes and minor enhancements.

The Mac update addresses a regression that could result in reachability checks to fail when using a fixed IP version for remote OpenVPN (or proxy) servers, while the Windows update includes a fix for VPN connections using non-standard MTU values. Also included for both platforms are a number of minor requested enhancements to the user interface and connection performance.

Version 1.7.16 Mac Release Notes:

Version 1.7.16 Windows Release Notes:

The 1.7.16 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.

Viscosity version 1.7.15 is now available for both Mac and Windows! This version includes U2F and PKCS#11 improvements, updated versions of both OpenVPN and OpenSSL, and a number of fixes and improvements for both platforms.

We've placed a focus on two-factor authentication for this release, with general improvements to Viscosity's U2F authentication support, including the ability to use U2F tokens from additional manufacturers. PKCS#11 support has also been improved in the Windows version, with smoother handling of problems that may arise when using a token or smartcard.

On the maintenance front, OpenVPN has been updated to version 2.4.7, which includes a number of small bug fixes. OpenSSL has also been updated to version 1.0.2r. The Windows release also includes an updated VPN network adapter driver with slightly improved performance, while the macOS release fixes an issue that could result in some VPN connections failing to try additional remote servers if the first one fails to connect.

Version 1.7.15 Mac Release Notes:

Version 1.7.15 Windows Release Notes:

The 1.7.15 update can be automatically installed from inside Viscosity, or downloaded and manually installed. For support with this version please visit our support section.