After months of work, we have a new stable release series!
If you build Tor from source, you can download the source
code for 0.4.4.5 on the
download page.
Packages should be available within the next several weeks, with a new Tor Browser by some time next week.

Tor 0.4.4.5 is the first stable release in the 0.4.4.x series. This series improves our guard selection algorithms, adds v3 onion balance support, improves the amount of code that can be disabled when running without relay support, and includes numerous small bugfixes and enhancements. It also lays the ground for some IPv6 features that we'll be developing more in the next (0.4.5) series.

Per our support policy, we support each stable release series for nine months after its first stable release, or three months after the first stable release of the next series: whichever is longer. This means that 0.4.4.x will be supported until around June 2021--or later, if 0.4.5.x is later than anticipated.

Note also that support for 0.4.2.x has just ended; support for 0.4.3 will continue until Feb 15, 2021. We still plan to continue supporting 0.3.5.x, our long-term stable series, until Feb 2022.

Below are the changes since 0.4.3.6-rc. For a complete list of changes since 0.4.4.4-rc, see the ChangeLog file.

Changes in version 0.4.4.5 - 2020-09-15

• Major features (Proposal 310, performance + security):
  • Implements Proposal 310, "Bandaid on guard selection". Proposal 310 solves load-balancing issues with older versions of the guard selection algorithm, and improves its security. Under this new algorithm, a newly selected guard never becomes Primary unless all previously sampled guards are unreachable. Implements recommendation from 32088. (Proposal 310 is linked to the CLAPS project researching optimal client location-aware path selections. This project is a collaboration between the UCLouvain Crypto Group, the U.S. Naval Research Laboratory, and Princeton University.)
• Major features (fallback directory list):
  • Replace the 148 fallback directories originally included in Tor 0.4.1.4-rc (of which around 105 are still functional) with a list of 144 fallbacks generated in July 2020. Closes ticket 40061.

After months of work, we have a new stable release series!

We have new releases today. If you build Tor from source, you can download the source code for 0.4.2.7 from the download page on the website. Packages should be available within the next several days, including a new Tor Browser.

We have two new stable releases today. If you build Tor from source, you can download the source code for 0.4.2.6 from the download page on our website. Packages should be available within the next several weeks, with a new Tor Browser by mid-February.

Ater months of work, we have a new stable release series! If you build Tor from source, you can download the source code for 0.4.2.5 on the website. Packages should be available within the next several weeks, with a new Tor Browser around January 7.

We have a new stable release today. If you build Tor from source, you can download the source code for 0.4.1.6 from the download page on the website. Packages should be available within the next several weeks, with a new Tor Browser in the next week or two.

This release backports several bugfixes to improve stability and correctness. Anyone experiencing build problems or crashes with 0.4.1.5, or experiencing reliability issues with single onion services, should upgrade.

Changes in version 0.4.1.6 - 2019-09-19

• Major bugfixes (crash, Linux, Android, backport from 0.4.2.1-alpha):
  • Tolerate systems (including some Android installations) where madvise and MADV_DONTDUMP are available at build-time, but not at run time. Previously, these systems would notice a failed syscall and abort. Fixes bug 31570; bugfix on 0.4.1.1-alpha.
  • Tolerate systems (including some Linux installations) where madvise and/or MADV_DONTFORK are available at build-time, but not at run time. Previously, these systems would notice a failed syscall and abort. Fixes bug 31696; bugfix on 0.4.1.1-alpha.
• Minor features (stem tests, backport from 0.4.2.1-alpha):
  • Change "make test-stem" so it only runs the stem tests that use tor. This change makes test-stem faster and more reliable. Closes ticket 31554.

After months of work, we have a new stable release series! If you build Tor from source, you can download the source code for 0.4.1.5 on the website. Packages should be available within the next several weeks, with a new Tor Browser in early September.

This is the first stable release in the 0.4.1.x series. This series adds experimental circuit-level padding, authenticated SENDME cells to defend against certain attacks, and several performance improvements to save on CPU consumption. It fixes bugs in bootstrapping and v3 onion services. It also includes numerous smaller features and bugfixes on earlier versions.

Per our support policy, we will support the 0.4.1.x series for nine months, or until three months after the release of a stable 0.4.2.x: whichever is longer. If you need longer-term support, please stick with 0.3.5.x, which will we plan to support until Feb 2022.

Below are the changes since 0.4.0.5. For a list of only the changes since 0.4.1.4-rc, see the ChangeLog file.

Changes in version 0.4.1.5 - 2019-08-20

• Directory authority changes:
  • The directory authority "dizum" has a new IP address. Closes ticket 31406.
• Major features (circuit padding):
  • Onion service clients now add padding cells at the start of their INTRODUCE and RENDEZVOUS circuits, to make those circuits' traffic look more like general purpose Exit traffic. The overhead for this is 2 extra cells in each direction for RENDEZVOUS circuits, and 1 extra upstream cell and 10 downstream cells for INTRODUCE circuits. This feature is only enabled when also supported by the circuit's middle node. (Clients may specify fixed middle nodes with the MiddleNodes option, and may force-disable this feature with the CircuitPadding option.) Closes ticket 28634.

After months of work, we have a new stable release series! If you build Tor from source, you can download the source code for 0.4.0.5 on the website. Packages should be available within the next several weeks, with a new Tor Browser likely later this month.

This is the first stable release in the 0.4.0.x series. It contains improvements for power management and bootstrap reporting, as well as preliminary backend support for circuit padding to prevent some kinds of traffic analysis. It also continues our work in refactoring Tor for long-term maintainability.

We have a new stable release today. If you build Tor from source, you can download the source code for Tor 0.3.4.9 from the download page on the website. Packages should be available within the next several weeks, with a new Tor Browser by mid-December.

Tor 0.3.4.9 is the second stable release in its series; it backports numerous fixes, including a fix for a bandwidth management bug that was causing memory exhaustion on relays. Anyone running an earlier version of Tor 0.3.4.9 should upgrade.

Changes in version 0.3.4.9 - 2018-11-02

• Major bugfixes (compilation, backport from 0.3.5.3-alpha):
  • Fix compilation on ARM (and other less-used CPUs) when compiling with OpenSSL before 1.1. Fixes bug 27781; bugfix on 0.3.4.1-alpha.
• Major bugfixes (mainloop, bootstrap, backport from 0.3.5.3-alpha):
  • Make sure Tor bootstraps and works properly if only the ControlPort is set. Prior to this fix, Tor would only bootstrap when a client port was set (Socks, Trans, NATD, DNS or HTTPTunnel port). Fixes bug 27849; bugfix on 0.3.4.1-alpha.

After months of work, we have a new stable release series! If you build Tor from source, you can download the source code for 0.3.4.8 on the download page of the website. Packages should be available within the next several weeks, with a new Tor Browser by some time next week.