/ doc / release-notes / release-notes-0.11.1.md
release-notes-0.11.1.md
  1  Bitcoin Core version 0.11.1 is now available from:
  2  
  3    <https://bitcoin.org/bin/bitcoin-core-0.11.1/>
  4  
  5  This is a new minor version release, bringing security fixes. It is recommended
  6  to upgrade to this version as soon as possible.
  7  
  8  Please report bugs using the issue tracker at github:
  9  
 10    <https://github.com/bitcoin/bitcoin/issues>
 11  
 12  Upgrading and downgrading
 13  =========================
 14  
 15  How to Upgrade
 16  --------------
 17  
 18  If you are running an older version, shut it down. Wait until it has completely
 19  shut down (which might take a few minutes for older versions), then run the
 20  installer (on Windows) or just copy over /Applications/Bitcoin-Qt (on Mac) or
 21  bitcoind/bitcoin-qt (on Linux).
 22  
 23  Downgrade warning
 24  ------------------
 25  
 26  Because release 0.10.0 and later makes use of headers-first synchronization and
 27  parallel block download (see further), the block files and databases are not
 28  backwards-compatible with pre-0.10 versions of Bitcoin Core or other software:
 29  
 30  * Blocks will be stored on disk out of order (in the order they are
 31  received, really), which makes it incompatible with some tools or
 32  other programs. Reindexing using earlier versions will also not work
 33  anymore as a result of this.
 34  
 35  * The block index database will now hold headers for which no block is
 36  stored on disk, which earlier versions won't support.
 37  
 38  If you want to be able to downgrade smoothly, make a backup of your entire data
 39  directory. Without this your node will need start syncing (or importing from
 40  bootstrap.dat) anew afterwards. It is possible that the data from a completely
 41  synchronised 0.10 node may be usable in older versions as-is, but this is not
 42  supported and may break as soon as the older version attempts to reindex.
 43  
 44  This does not affect wallet forward or backward compatibility. There are no
 45  known problems when downgrading from 0.11.x to 0.10.x.
 46  
 47  Notable changes
 48  ===============
 49  
 50  Fix buffer overflow in bundled upnp
 51  ------------------------------------
 52  
 53  Bundled miniupnpc was updated to 1.9.20151008. This fixes a buffer overflow in
 54  the XML parser during initial network discovery.
 55  
 56  Details can be found here: http://talosintel.com/reports/TALOS-2015-0035/
 57  
 58  This applies to the distributed executables only, not when building from source or
 59  using distribution provided packages.
 60  
 61  Additionally, upnp has been disabled by default. This may result in a lower
 62  number of reachable nodes on IPv4, however this prevents future libupnpc
 63  vulnerabilities from being a structural risk to the network
 64  (see https://github.com/bitcoin/bitcoin/pull/6795).
 65  
 66  Test for LowS signatures before relaying
 67  -----------------------------------------
 68  
 69  Make the node require the canonical 'low-s' encoding for ECDSA signatures when
 70  relaying or mining.  This removes a nuisance malleability vector.
 71  
 72  Consensus behavior is unchanged.
 73  
 74  If widely deployed this change would eliminate the last remaining known vector
 75  for nuisance malleability on SIGHASH_ALL P2PKH transactions. On the down-side
 76  it will block most transactions made by sufficiently out of date software.
 77  
 78  Unlike the other avenues to change txids on transactions this
 79  one was randomly violated by all deployed bitcoin software prior to
 80  its discovery. So, while other malleability vectors where made
 81  non-standard as soon as they were discovered, this one has remained
 82  permitted. Even BIP62 did not propose applying this rule to
 83  old version transactions, but conforming implementations have become
 84  much more common since BIP62 was initially written.
 85  
 86  Bitcoin Core has produced compatible signatures since a28fb70e in
 87  September 2013, but this didn't make it into a release until 0.9
 88  in March 2014; Bitcoinj has done so for a similar span of time.
 89  Bitcoinjs and electrum have been more recently updated.
 90  
 91  This does not replace the need for BIP62 or similar, as miners can
 92  still cooperate to break transactions.  Nor does it replace the
 93  need for wallet software to handle malleability sanely[1]. This
 94  only eliminates the cheap and irritating DOS attack.
 95  
 96  [1] On the Malleability of Bitcoin Transactions
 97  Marcin Andrychowicz, Stefan Dziembowski, Daniel Malinowski, Łukasz Mazurek
 98  http://fc15.ifca.ai/preproceedings/bitcoin/paper_9.pdf
 99  
100  Minimum relay fee default increase
101  -----------------------------------
102  
103  The default for the `-minrelaytxfee` setting has been increased from `0.00001`
104  to `0.00005`.
105  
106  This is necessitated by the current transaction flooding, causing
107  outrageous memory usage on nodes due to the mempool ballooning. This is a
108  temporary measure, bridging the time until a dynamic method for determining
109  this fee is merged (which will be in 0.12).
110  
111  (see https://github.com/bitcoin/bitcoin/pull/6793, as well as the 0.11
112  release notes, in which this value was suggested)
113  
114  0.11.1 Change log
115  =================
116  
117  Detailed release notes follow. This overview includes changes that affect
118  behavior, not code moves, refactors and string updates. For convenience in locating
119  the code changes and accompanying discussion, both the pull request and
120  git merge commit are mentioned.
121  
122  - #6438 `2531438` openssl: avoid config file load/race
123  - #6439 `980f820` Updated URL location of netinstall for Debian
124  - #6384 `8e5a969` qt: Force TLS1.0+ for SSL connections
125  - #6471 `92401c2` Depends: bump to qt 5.5
126  - #6224 `93b606a` Be even stricter in processing unrequested blocks
127  - #6571 `100ac4e` libbitcoinconsensus: avoid a crash in multi-threaded environments
128  - #6545 `649f5d9` Do not store more than 200 timedata samples.
129  - #6694 `834e299` [QT] fix thin space word wrap line break issue
130  - #6703 `1cd7952` Backport bugfixes to 0.11
131  - #6750 `5ed8d0b` Recent rejects backport to v0.11
132  - #6769 `71cc9d9` Test LowS in standardness, removes nuisance malleability vector.
133  - #6789 `b4ad73f` Update miniupnpc to 1.9.20151008
134  - #6785 `b4dc33e` Backport to v0.11: In (strCommand == "tx"), return if AlreadyHave()
135  - #6412 `0095b9a` Test whether created sockets are select()able
136  - #6795 `4dbcec0` net: Disable upnp by default
137  - #6793 `e7bcc4a` Bump minrelaytxfee default
138  
139  Credits
140  =======
141  
142  Thanks to everyone who directly contributed to this release:
143  
144  - Adam Weiss
145  - Alex Morcos
146  - Casey Rodarmor
147  - Cory Fields
148  - fanquake
149  - Gregory Maxwell
150  - Jonas Schnelli
151  - J Ross Nicoll
152  - Luke Dashjr
153  - Pavel Janík
154  - Pavel Vasin
155  - Peter Todd
156  - Pieter Wuille
157  - randy-waterhouse
158  - Ross Nicoll
159  - Suhas Daftuar
160  - tailsjoin
161  - ฿tcDrak
162  - Tom Harding
163  - Veres Lajos
164  - Wladimir J. van der Laan
165  
166  And those who contributed additional code review and/or security research:
167  
168  - timothy on IRC for reporting the issue
169  - Vulnerability in miniupnp discovered by Aleksandar Nikolic of Cisco Talos
170  
171  As well as everyone that helped translating on [Transifex](https://www.transifex.com/projects/p/bitcoin/).
172