release of Tor. If you want to see more detailed descriptions of the
changes in each development snapshot, see the ChangeLog file.
-Changes in version 0.4.3.3-alpha - 2020-03-18
- Tor 0.4.3.3-alpha fixes several bugs in previous releases, including
- TROVE-2020-002, a major denial-of-service vulnerability that affected
- all released Tor instances since 0.2.1.5-alpha. Using this
- vulnerability, an attacker could cause Tor instances to consume a huge
- amount of CPU, disrupting their operations for several seconds or
- minutes. This attack could be launched by anybody against a relay, or
- by a directory cache against any client that had connected to it. The
- attacker could launch this attack as much as they wanted, thereby
- disrupting service or creating patterns that could aid in traffic
- analysis. This issue was found by OSS-Fuzz, and is also tracked
- as CVE-2020-10592.
-
- We do not have reason to believe that this attack is currently being
- exploited in the wild, but nonetheless we advise everyone to upgrade
- as soon as packages are available.
-
- o Major bugfixes (security, denial-of-service):
- - Fix a denial-of-service bug that could be used by anyone to
- consume a bunch of CPU on any Tor relay or authority, or by
- directories to consume a bunch of CPU on clients or hidden
- services. Because of the potential for CPU consumption to
- introduce observable timing patterns, we are treating this as a
- high-severity security issue. Fixes bug 33119; bugfix on
- 0.2.1.5-alpha. Found by OSS-Fuzz. We are also tracking this issue
- as TROVE-2020-002 and CVE-2020-10592.
-
- o Major bugfixes (circuit padding, memory leak):
- - Avoid a remotely triggered memory leak in the case that a circuit
- padding machine is somehow negotiated twice on the same circuit.
- Fixes bug 33619; bugfix on 0.4.0.1-alpha. Found by Tobias Pulls.
- This is also tracked as TROVE-2020-004 and CVE-2020-10593.
-
- o Major bugfixes (directory authority):
- - Directory authorities will now send a 503 (not enough bandwidth)
- code to clients when under bandwidth pressure. Known relays and
- other authorities will always be answered regardless of the
- bandwidth situation. Fixes bug 33029; bugfix on 0.1.2.5-alpha.
-
- o Minor features (diagnostic):
- - Improve assertions and add some memory-poisoning code to try to
- track down possible causes of a rare crash (32564) in the EWMA
- code. Closes ticket 33290.
-
- o Minor features (directory authorities):
- - Directory authorities now reject descriptors from relays running
- Tor versions from the 0.2.9 and 0.4.0 series. The 0.3.5 series is
- still allowed. Resolves ticket 32672. Patch by Neel Chauhan.
-
- o Minor features (usability):
- - Include more information when failing to parse a configuration
- value. This should make it easier to tell what's going wrong when
- a configuration file doesn't parse. Closes ticket 33460.
-
- o Minor bugfix (relay, configuration):
- - Warn if the ContactInfo field is not set, and tell the relay
- operator that not having a ContactInfo field set might cause their
- relay to get rejected in the future. Fixes bug 33361; bugfix
- on 0.1.1.10-alpha.
-
- o Minor bugfixes (coding best practices checks):
- - Allow the "practracker" script to read unicode files when using
- Python 2. We made the script use unicode literals in 0.4.3.1-alpha,
- but didn't change the codec for opening files. Fixes bug 33374;
- bugfix on 0.4.3.1-alpha.
-
- o Minor bugfixes (continuous integration):
- - Remove the buggy and unused mirroring job. Fixes bug 33213; bugfix
- on 0.3.2.2-alpha.
-
- o Minor bugfixes (onion service v3, client):
- - Remove a BUG() warning that would cause a stack trace if an onion
- service descriptor was freed while we were waiting for a
- rendezvous circuit to complete. Fixes bug 28992; bugfix
- on 0.3.2.1-alpha.
-
- o Minor bugfixes (onion services v3):
- - Fix an assertion failure that could result from a corrupted
- ADD_ONION control port command. Found by Saibato. Fixes bug 33137;
- bugfix on 0.3.3.1-alpha. This issue is also tracked
- as TROVE-2020-003.
-
- o Documentation (manpage):
- - Alphabetize the Server and Directory server sections of the tor
- manpage. Also split Statistics options into their own section of
- the manpage. Closes ticket 33188. Work by Swati Thacker as part of
- Google Season of Docs.
- - Document the __OwningControllerProcess torrc option and specify
- its polling interval. Resolves issue 32971.
-
- o Testing (Travis CI):
- - Remove a redundant distcheck job. Closes ticket 33194.
- - Sort the Travis jobs in order of speed: putting the slowest jobs
- first takes full advantage of Travis job concurrency. Closes
- ticket 33194.
- - Stop allowing the Chutney IPv6 Travis job to fail. This job was
- previously configured to fast_finish (which requires
- allow_failure), to speed up the build. Closes ticket 33195.
- - When a Travis chutney job fails, use chutney's new "diagnostics.sh"
- tool to produce detailed diagnostic output. Closes ticket 32792.
-
Changes in version 0.4.2.7 - 2020-03-18
This is the third stable release in the 0.4.2.x series. It backports