==============

lxml changelog

==============

7.0.0 (2026-??-??)

==================

Features added

--------------

* ``CDATA`` objects gained a string representation.

Bugs fixed

----------

* LP#2164984: Returning non-element types from a parser target in ``XMLDTDID()`` could crash.

* LP#2165904: Content of PIs and comments set through their ``.text`` property was not validated.

* A few out-of-memory cases now raise ``MemoryError`` with libxml2 2.13+.

7.0.0b1 (2026-08-22)

====================

Bugs fixed

----------

* LP#2143321: A ``NameError`` in ``doctestcompare`` when the doctests are processed

by a non-standard module.

Original patch by Rahul Kumar.

* GH#492: Failures in ``htmldiff()`` to string-join the diff result are now propagated

instead of silently returning an empty result.

Patch by Juan Carlos Carvajal B.

Other changes

-------------

* Built using Cython 3.3.0.

7.0.0a3 (2026-06-16)

====================

Features added

--------------

* ``.find()`` and ``.findall()`` now take advantage of their read-locked tree

to skip tree modification checks, making them visibly faster.

* Python Element proxy instantiation was tuned another bit to shave off more of the

performance disadvantages added by tree locking.

* The path compilation cache used by ElementPath uses an LRU eviction scheme.

It previously just cleared the whole cache when overflowing.

Bugs fixed

----------

* Attribute iteration now remembers a safe integer index instead of a tree attribute pointer

that is potentially subject of user side modifications. This may make attribute iteration

slightly slower for long sequences of attributes but allows for attribute manipulation

between iteration steps, giving similar iteration+manipulation semantics as Python lists.

* Several issues (race conditions, memory leaks on error handling, crashes)

were found via an automated review and subsequently resolved.

Review contributed by devdanzin.

7.0.0a2 (2026-06-09)

====================

Features added

--------------

* GH#511: The ElementPath implementation (``.find()`` etc) was rewritten based on

native traversal of the libxml2 tree instead of passing through Element proxy

objects. This makes some path operations like child steps or predicate evaluation

several times faster. Indexing can be more than 100x faster.

Note that some operations are also slower due to the new lock usages in lxml 7.0.

Usually, the more selective the path, the faster it runs.

Original idea and implementation by mahomaho.

7.0.0a1 (2026-05-29)

====================

Features added

--------------

* GH#477, LP#2111289: Experimental support for freethreading Python is enabled

in Python 3.14t and later.

* GH#466: The shared parser name dict is now local to a parser (as opposed to global),

which allows to control its lifetime and cross-document usage more easily.

It is now also unbounded in size if the ``huge_tree=True`` option is provided.

* The default chunk size for reading from file-likes in ``iterparse()`` was increased

from 32 KiB to 64 KiB and is now configurable with a new ``chunk_size`` argument.

* Writing to Python file objects minimises data copying by passing buffers around.

* GH#502: Predicate evaluation in ``ElementPath`` (``.find*()``) is faster.

* HTML diffing is faster, following optimisations in CPython 3.15.

* If multiple Python exceptions get raised from within an lxml operation, they no longer

overwrite old ones but get stacked in the exception context of the latest exception.

Bugs fixed

----------

* Reading from file-like objects that start with a UTF-32 BOM failed to detect the BOM.

Other changes

-------------

* Support for Python 3.8 was removed. Python 3.9 will continue to be supported for

several years due to its usage in LTS Linux distributions.

* Usage on PyPy can currently crash due to the Freethreading Python changes.

This is expected to get fixed in the further releases towards 7.0 final.

* Some internal adaptations were made for libxml2 2.14.x and 2.15.x.

* The ``xmlDict...`` C functions of libxml2 are now declared in ``tree.pxd``.

They remain in ``xmlparser.pxd`` for legacy reasons but Cython code that uses them

should migrate the import to ``tree.pxd``.

* The list of software licenses in LICENSES.txt was clarified and updated

to match the actual set of software being shipped.

* Built using Cython 3.2.5.

6.1.3 (2026-09-02)

==================

Bugs fixed

----------

* LP#2165901: External parameter entity parsing was allowed by default

(with ``resolve_entities="internal"``).

Issue found by Tomer Fichman.

6.1.2 (2026-08-18)

==================

* GH#526: Some build files were missing in the sdist.

Patch by Nicola Soranzo.

* Some minor corrections for error handling cases.

Other changes

-------------

* Built with Cython 3.2.9.

6.1.1 (2026-05-18)

==================

Bugs fixed

----------

* The known link attributes in ``lxml.html.defs.link_attrs`` were missing ``xlink:href``,

which can be used for URL bypass attacks in embedded SVG/MathML/etc. content.

https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-4jhm-jv67-739f

* The Linux wheels use a patched libxslt 1.1.43, fixing CVE-2025-7424 and CVE-2025-11731.

* The Windows wheels use libxslt 1.1.45, fixing CVE-2025-7424 and CVE-2025-11731.

6.1.0 (2026-04-17)

==================

This release fixes a possible external entity injection (XXE) vulnerability in

``iterparse()`` and the ``ETCompatXMLParser``.

Features added

--------------

* GH#486: The HTML ARIA accessibility attributes were added to the set of safe attributes

in ``lxml.html.defs``. This allows ``lxml_html_clean`` to pass them through.

Patch by oomsveta.

* The default chunk size for reading from file-likes in ``iterparse()`` is now configurable

with a new ``chunk_size`` argument.

Bugs fixed

----------

* LP#2146291: The ``resolve_entities`` option was still set to ``True`` for

``iterparse`` and ``ETCompatXMLParser``, allowing for external entity injection (XXE)

when using these parsers without setting this option explicitly.

The default was now changed to ``'internal'`` only (as for the normal XML and HTML parsers

since lxml 5.0).

Issue found by Sihao Qiu as CVE-2026-41066.

6.0.4 (2026-04-12)

==================

Bugs fixed

----------

* LP#2148019: Spurious MemoryError during namespace cleanup.

6.0.3 (2026-04-09)

==================

Bugs fixed

----------

* Several out of memory error cases now raise ``MemoryError`` that were not handled before.

* Slicing with large step values (outside of ``+/- sys.maxsize``) could trigger undefined C behaviour.

* LP#2125399: Some failing tests were fixed or disabled in PyPy.

* LP#2138421: Memory leak in error cases when setting the ``public_id`` or ``system_url`` of a document.

* Memory leak in case of a memory allocation failure when copying document subtrees.

* When mapping an XPath result to Python failed, the result memory could leak.

* When preparing an XSLT transform failed, the XSLT parameter memory could leak.

Other changes

-------------

* Built using Cython 3.2.4.

* Binary wheels use zlib 1.3.2.

6.0.2 (2025-09-21)

==================

Bugs fixed

----------

* LP#2125278: Compilation with libxml2 2.15.0 failed.

Original patch by Xi Ruoyao.

* Setting ``decompress=True`` in the parser had no effect in libxml2 2.15.

* Binary wheels on Linux and macOS use the library version libxml2 2.14.6.

See https://gitlab.gnome.org/GNOME/libxml2/-/releases/v2.14.6

* Test failures in libxml2 2.15.0 were fixed.

Other changes

-------------

* Binary wheels for Py3.9-3.11 on the ``riscv64`` architecture were added.

* Error constants were updated to match libxml2 2.15.0.

* Built using Cython 3.1.4.

6.0.1 (2025-08-22)

==================

Bugs fixed

----------

* LP#2116333: ``lxml.sax._getNsTag()`` could fail with an exception on malformed input.

* GH#467: Some test adaptations were made for libxml2 2.15.

Patch by Nick Wellnhofer.

* LP2119510, GH#473: A Python compatibility test was fixed for Python 3.14+.

Patch by Lumír Balhar.

* GH#471: Wheels for "riscv64" on recent Python versions were added.

Patch by ffgan.

* GH#469: The wheel build no longer requires the ``wheel`` package unconditionally.

Patch by Miro Hrončok.

* Binary wheels use the library version libxml2 2.14.5.

See https://gitlab.gnome.org/GNOME/libxml2/-/releases/v2.14.5

* Windows binary wheels continue to use a security patched library version libxml2 2.11.9.

6.0.0 (2025-06-26)

==================

Features added

--------------

* GH#463: ``lxml.html.diff`` is faster and provides structurally better diffs.

Original patch by Steven Fernandez.

* GH#405: The factories ``Element`` and ``ElementTree`` can now be used in type hints.

* GH#448: Parsing from ``memoryview`` and other buffers is supported to allow zero-copy parsing.

* GH#437: ``lxml.html.builder`` was missing several HTML5 tag names.

Patch by Nick Tarleton.

* GH#458: ``CDATA`` can now be written into the incremental ``xmlfile()`` writer.

Original patch by Lane Shaw.

* A new parser option ``decompress=False`` was added that controls the automatic

input decompression when using libxml2 2.15.0 or later. Disabling this option

by default will effectively prevent decompression bombs when handling untrusted

input. Code that depends on automatic decompression must enable this option.

Note that libxml2 2.15.0 was not released yet, so this option currently has no

effect but can already be used.

* The set of compile time / runtime supported libxml2 feature names is available as

``etree.LIBXML_COMPILED_FEATURES`` and ``etree.LIBXML_FEATURES``.

This currently includes

``catalog``, ``ftp``, ``html``, ``http``, ``iconv``, ``icu``,

``lzma``, ``regexp``, ``schematron``, ``xmlschema``, ``xpath``, ``zlib``.

Bugs fixed

----------

* GH#353: Predicates in ``.find*()`` could mishandle tag indices if a default namespace is provided.

Original patch by Luise K.

* GH#272: The ``head`` and ``body`` properties of ``lxml.html`` elements failed if no such element

was found. They now return ``None`` instead.

Original patch by FVolral.

* Tag names provided by code (API, not data) that are longer than ``INT_MAX``

could be truncated or mishandled in other ways.

* ``.text_content()`` on ``lxml.html`` elements accidentally returned a "smart string"

without additional information. It now returns a plain string.

* LP#2109931: When building lxml with coverage reporting, it now disables the ``sys.monitoring``

support due to the lack of support in https://github.com/nedbat/coveragepy/issues/1790

Other changes

-------------

* Support for Python < 3.8 was removed.

* Parsing directly from zlib (or lzma) compressed data is now considered an optional

feature in lxml. It may get removed from libxml2 at some point for security reasons

(compression bombs) and is therefore no longer guaranteed to be available in lxml.

As of this release, zlib support is still normally available in the binary wheels

but may get disabled or removed in later (x.y.0) releases. To test the availability,

use ``"zlib" in etree.LIBXML_FEATURES``.

* The ``Schematron`` class is deprecated and will become non-functional in a future lxml version.

The feature will soon be removed from libxml2 and stop being available.

* GH#438: Wheels include the ``arm7l`` target.

* GH#465: Windows wheels include the ``arm64`` target.

Patch by Finn Womack.

* Binary wheels use the library versions libxml2 2.14.4 and libxslt 1.1.43.

Note that this disables direct HTTP and FTP support for parsing from URLs.

Use Python URL request tools instead (which usually also support HTTPS).

To test the availability, use ``"http" in etree.LIBXML_FEATURES``.

* Windows binary wheels use the library versions libxml2 2.11.9, libxslt 1.1.39 and libiconv 1.17.

They are now based on VS-2022.

* Built using Cython 3.1.2.

* The debug methods ``MemDebug.dump()`` and ``MemDebug.show()`` were removed completely.

libxml2 2.13.0 discarded this feature.

5.4.0 (2025-04-22)

==================

Bugs fixed

----------

* LP#2107279: Binary wheels use libxml2 2.13.8 and libxslt 1.1.43 to resolve several CVEs.

(Binary wheels for Windows continue to use a patched libxml2 2.11.9 and libxslt 1.1.39.)

Issue found by Anatoly Katyushin.

5.3.2 (2025-04-05)

==================

This release resolves CVE-2025-24928 as described in

https://gitlab.gnome.org/GNOME/libxml2/-/issues/847

Bugs fixed

----------

* Binary wheels use libxml2 2.12.10 and libxslt 1.1.42.

* Binary wheels for Windows use a patched libxml2 2.11.9 and libxslt 1.1.39.

5.3.1 (2025-02-09)

==================

Bugs fixed

----------

* GH#440: Some tests were adapted for libxml2 2.14.0.

Patch by Nick Wellnhofer.

* LP#2097175: ``DTD(external_id="…")`` erroneously required a byte string as ID value.

* GH#450: ``iterparse()`` internally triggered the `DeprecationWarning`` added in lxml 5.3.0 when parsing HTML.

Other changes

-------------

* GH#442: Binary wheels for macOS no longer use the linker flag ``-flat_namespace``.

5.3.0 (2024-08-10)

==================

Features added

--------------

* GH#421: Nested ``CDATA`` sections are no longer rejected but split on output

to represent ``]]>`` correctly.

Patch by Gertjan Klein.

Bugs fixed

----------

* LP#2060160: Attribute values serialised differently in ``xmlfile.element()`` and ``xmlfile.write()``.

* LP#2058177: The ISO-Schematron implementation could fail on unknown prefixes.

Patch by David Lakin.

Other changes

-------------

* LP#2067707: The ``strip_cdata`` option in ``HTMLParser()`` turned out to be useless and is now deprecated.

* Binary wheels use the library versions libxml2 2.12.9 and libxslt 1.1.42.

* Windows binary wheels use the library versions libxml2 2.11.8 and libxslt 1.1.39.

* Built with Cython 3.0.11.

5.2.2 (2024-05-12)

==================

Bugs fixed

----------

* GH#417: The ``test_feed_parser`` test could fail if ``lxml_html_clean`` was not installed.

It is now skipped in that case.

* LP#2059910: The minimum CPU architecture for the Linux x86 binary wheels was set back to

"core2", without SSE 4.2.

* If libxml2 uses iconv, the compile time version is available as `etree.ICONV_COMPILED_VERSION`.

5.2.1 (2024-04-02)

==================

Bugs fixed

----------

* LP#2059910: The minimum CPU architecture for the Linux x86 binary wheels was set back to

"core2", but with SSE 4.2 enabled.

* LP#2059977: ``Element.iterfind("//absolute_path")`` failed with a ``SyntaxError``

where it should have issued a warning.

* GH#416: The documentation build was using the non-standard ``which`` command.

Patch by Michał Górny.

5.2.0 (2024-03-30)

==================

Other changes

-------------

* LP#1958539: The ``lxml.html.clean`` implementation suffered from several (only if used)

security issues in the past and was now extracted into a separate library:

https://github.com/fedora-python/lxml_html_clean

Projects that use lxml without "lxml.html.clean" will not notice any difference,

except that they won't have potentially vulnerable code installed.

The module is available as an "extra" setuptools dependency "lxml[html_clean]",

so that Projects that need "lxml.html.clean" will need to switch their requirements

from "lxml" to "lxml[html_clean]", or install the new library themselves.

* The minimum CPU architecture for the Linux x86 binary wheels was upgraded to

"sandybridge" (launched 2011), and glibc 2.28 / gcc 12 (manylinux_2_28) wheels were added.

* Built with Cython 3.0.10.

5.1.1 (2024-03-28)

==================

Bugs fixed

----------

* LP#2048920: ``iterlinks()`` in ``lxml.html`` rejected ``bytes`` input in 5.1.0.

* High source line numbers from the parser are no longer truncated

(up to a C ``long``) when using libxml2 2.11 or later.

Other changes

-------------

* GH#407: A compatibility test was adapted to recent expat versions.

Patch by Miro Hrončok.

* Binary wheels use the library versions libxml2 2.12.6 and libxslt 1.1.39.

* Windows binary wheels use the library versions libxml2 2.11.7 and libxslt 1.1.39.

* Built with Cython 3.0.9.

5.1.0 (2024-01-05)

==================

Features added

--------------

* Parsing ASCII strings is slightly faster.

Bugs fixed

----------

* GH#349: The HTML ``Cleaner()`` interpreted an accidentally provided string parameter

for the ``host_whitelist`` as list of characters and silently failed to reject any hosts.

Passing a non-collection is now rejected.

Other changes

-------------

* Support for Python 2.7 and Python versions < 3.6 was removed.

* The wheel build was migrated to use ``cibuildwheel``.

Patch by Primož Godec.

5.0.2 (2024-03-28)

==================

Other changes

-------------

* GH#407: A compatibility test was adapted to recent expat versions.

Patch by Miro Hrončok.

* Binary wheels use the library versions libxml2 2.12.6 and libxslt 1.1.39.

* Built with Cython 3.0.9.

5.0.1 (2024-01-05)

==================

Bugs fixed

----------

* LP#2046208: Parsing non-BMP Python Unicode strings could fail on macOS.

* LP#2044225: When incrementally parsing broken HTML, reporting start events on

missing structural tags failed and could lead to subsequent exceptions.

* LP#2045435: Some (not all) issues with stricter C compilers were resolved.

* The binary wheels in the 5.0.0 release did not validate cleanly (but installed ok).

.. _latest_release:

5.0.0 (2023-12-29)

==================

Features added

--------------

* Character escaping in ``C14N2`` serialisation now uses a single pass over the text

instead of searching for each unescaped character separately.

* Early support for Python 3.13a2 was added.

Bugs fixed

----------

* LP#1976304: The ``Element.addnext()`` method previously inserted the new element

before existing tail text. The tail text of both sibling elements now stays on

the respective elements.

* LP#1980767, GH#379: ``TreeBuilder.close()`` could fail with a ``TypeError`` after

parsing incorrect input. Original patch by Enrico Minack.

* ``Element.itertext(with_tail=False)`` returned the tail text of comments and

processing instructions, despite the explicit option.

* GH#370: A crash with recent libxml2 2.11.x versions was resolved.

Patch by Michael Schlenker.

* A compile problem with recent libxml2 2.12.x versions was resolved.

* The internal exception handling in C callbacks was improved for Cython 3.0.

* The exception declarations of ``xmlInputReadCallback``, ``xmlInputCloseCallback``,

``xmlOutputWriteCallback`` and ``xmlOutputCloseCallback`` in ``tree.pxd`` were

corrected to prevent running Python code or calling into the C-API with a live

exception set.

* GH#385: The long deprecated ``unittest.m̀akeSuite()`` function is no longer used.

Patch by Miro Hrončok.

* LP#1522052: A file-system specific test is now optional and should no longer fail

on systems that don't support it.

* GH#392: Some tests were adapted for libxml2 2.13.

Patch by Nick Wellnhofer.

* Contains all fixes from lxml 4.9.4.

Other changes

-------------

* LP#1742885: lxml no longer expands external entities (XXE) by default to prevent

the security risk of loading arbitrary files and URLs. If this feature is needed,

it can be enabled in a backwards compatible way by using a parser with the option

``resolve_entities=True``. The new default is ``resolve_entities='internal'``.

* With libxml2 2.10.4 and later (as provided by the lxml 5.0 binary wheels),

parsing HTML tags with "prefixes" no longer builds a namespace dictionary

in ``nsmap`` but considers the ``prefix:name`` string the actual tag name.

With older libxml2 versions, since 2.9.11, the prefix was removed. Before

that, the prefix was parsed as XML prefix.

lxml 5.0 does not try to hide this difference but now changes the ElementPath

implementation to let ``element.find("part1:part2")`` search for the tag

``part1:part2`` in documents parsed as HTML, instead of looking only for ``part2``.

* LP#2024343: The validation of the schema file itself is now optional in the

ISO-Schematron implementation. This was done because some lxml distributions

discard the RNG validation schema file due to licensing issues. The validation

can now always be disabled with ``Schematron(..., validate_schema=False)``.

It is enabled by default if available and disabled otherwise. The module

constant ``lxml.isoschematron.schematron_schema_valid_supported`` can be used

to detect whether schema file validation is available.

* Some redundant and long deprecated methods were removed:

``parser.setElementClassLookup()``,

``xslt_transform.apply()``,

``xpath.evaluate()``.

* Some incorrect declarations were removed from ``python.pxd``. In general, this file

should not be used by external Cython code. Use the C-API declarations provided by

Cython itself instead.

* Binary wheels use the library versions libxml2 2.12.3 and libxslt 1.1.39.

* Built with Cython 3.0.7, updated to follow recent changes in Cython 3.1-dev.

4.9.4 (2023-12-19)

==================

Bugs fixed

----------

* LP#2046398: Inserting/replacing an ancestor into a node's children could loop indefinitely.

* LP#1980767, GH#379: ``TreeBuilder.close()`` could fail with a ``TypeError`` after

parsing incorrect input. Original patch by Enrico Minack.

* LP#1522052: A file-system specific test is now optional and should no longer fail

on systems that don't support it.

Other changes

-------------

* Wheels include zlib 1.3, libxml2 2.10.3 and libxslt 1.1.39

(zlib 1.2.12, libxml2 2.10.3 and libxslt 1.1.37 on Windows).

* Built with Cython 0.29.37.

4.9.3 (2023-07-05)

==================

Bugs fixed

----------

* LP#2008911: ``lxml.objectify`` accepted non-decimal numbers like ``²²²`` as integers.

* A memory leak in ``lxml.html.clean`` was resolved by switching to Cython 0.29.34+.

* GH#348: URL checking in the HTML cleaner was improved.

Patch by Tim McCormack.

* GH#371, GH#373: Some regex strings were changed to raw strings to fix Python warnings.

Patches by Jakub Wilk and Anthony Sottile.

Other changes

-------------

* Wheels include zlib 1.2.13, libxml2 2.10.3 and libxslt 1.1.38

(zlib 1.2.12, libxml2 2.10.3 and libxslt 1.1.37 on Windows).

* Built with Cython 0.29.36 to adapt to changes in Python 3.12.

4.9.2 (2022-12-13)

==================

Bugs fixed

----------

* CVE-2022-2309: A Bug in libxml2 2.9.1[0-4] could let namespace declarations

from a failed parser run leak into later parser runs. This bug was worked around

in lxml and resolved in libxml2 2.10.0.

https://gitlab.gnome.org/GNOME/libxml2/-/issues/378

Other changes

-------------

* LP#1981760: ``Element.attrib`` now registers as ``collections.abc.MutableMapping``.

* lxml now has a static build setup for macOS on ARM64 machines (not used for building wheels).

Patch by Quentin Leffray.

4.9.1 (2022-07-01)

==================

Bugs fixed

----------

* A crash was resolved when using ``iterwalk()`` (or ``canonicalize()``)

after parsing certain incorrect input. Note that ``iterwalk()`` can crash

on *valid* input parsed with the same parser *after* failing to parse the

incorrect input.

4.9.0 (2022-06-01)

==================

Bugs fixed

----------

* GH#341: The mixin inheritance order in ``lxml.html`` was corrected.

Patch by xmo-odoo.

Other changes

-------------

* Built with Cython 0.29.30 to adapt to changes in Python 3.11 and 3.12.

* Wheels include zlib 1.2.12, libxml2 2.9.14 and libxslt 1.1.35

(libxml2 2.9.12+ and libxslt 1.1.34 on Windows).

* GH#343: Windows-AArch64 build support in Visual Studio.

Patch by Steve Dower.

4.8.0 (2022-02-17)

==================

Features added

--------------

* GH#337: Path-like objects are now supported throughout the API instead of just strings.

Patch by Henning Janssen.

* The ``ElementMaker`` now supports ``QName`` values as tags, which always override

the default namespace of the factory.

Bugs fixed

----------

* GH#338: In lxml.objectify, the XSI float annotation "nan" and "inf" were spelled in

lower case, whereas XML Schema datatypes define them as "NaN" and "INF" respectively.

Patch by Tobias Deiminger.

Other changes

-------------

* Built with Cython 0.29.28.

4.7.1 (2021-12-13)

==================

Features added

--------------

* Chunked Unicode string parsing via ``parser.feed()`` now encodes the input data

to the native UTF-8 encoding directly, instead of going through ``Py_UNICODE`` /

``wchar_t`` encoding first, which previously required duplicate recoding in most cases.

Bugs fixed

----------

* The standard namespace prefixes were mishandled during "C14N2" serialisation on Python 3.

See https://mail.python.org/archives/list/lxml@python.org/thread/6ZFBHFOVHOS5GFDOAMPCT6HM5HZPWQ4Q/

* ``lxml.objectify`` previously accepted non-XML numbers with underscores (like "1_000")

as integers or float values in Python 3.6 and later. It now adheres to the number

format of the XML spec again.

* LP#1939031: Static wheels of lxml now contain the header files of zlib and libiconv

(in addition to the already provided headers of libxml2/libxslt/libexslt).

Other changes

-------------

* Wheels include libxml2 2.9.12+ and libxslt 1.1.34 (also on Windows).

4.7.0 (2021-12-13)

==================

* Release retracted due to missing files in lxml/includes/.

4.6.5 (2021-12-12)

==================

Bugs fixed

----------

* A vulnerability (GHSL-2021-1038) in the HTML cleaner allowed sneaking script

content through SVG images (CVE-2021-43818).

* A vulnerability (GHSL-2021-1037) in the HTML cleaner allowed sneaking script

content through CSS imports and other crafted constructs (CVE-2021-43818).

4.6.4 (2021-11-01)

==================

Features added

--------------

* GH#317: A new property ``system_url`` was added to DTD entities.

Patch by Thirdegree.

* GH#314: The ``STATIC_*`` variables in ``setup.py`` can now be passed via env vars.

Patch by Isaac Jurado.

4.6.3 (2021-03-21)

==================

Bugs fixed

----------

* A vulnerability (CVE-2021-28957) was discovered in the HTML Cleaner by Kevin Chung,

which allowed JavaScript to pass through. The cleaner now removes the HTML5

``formaction`` attribute.

4.6.2 (2020-11-26)

==================

Bugs fixed

----------

* A vulnerability (CVE-2020-27783) was discovered in the HTML Cleaner by Yaniv Nizry,

which allowed JavaScript to pass through. The cleaner now removes more sneaky

"style" content.

4.6.1 (2020-10-18)

==================

Bugs fixed

----------

* A vulnerability was discovered in the HTML Cleaner by Yaniv Nizry, which allowed

JavaScript to pass through. The cleaner now removes more sneaky "style" content.

4.6.0 (2020-10-17)

==================

Features added

--------------

* GH#310: ``lxml.html.InputGetter`` supports ``__len__()`` to count the number of input fields.

Patch by Aidan Woolley.

* ``lxml.html.InputGetter`` has a new ``.items()`` method to ease processing all input fields.

* ``lxml.html.InputGetter.keys()`` now returns the field names in document order.

* GH-309: The API documentation is now generated using ``sphinx-apidoc``.

Patch by Chris Mayo.

Bugs fixed

----------

* LP#1869455: C14N 2.0 serialisation failed for unprefixed attributes

when a default namespace was defined.

* ``TreeBuilder.close()`` raised ``AssertionError`` in some error cases where it

should have raised ``XMLSyntaxError``. It now raises a combined exception to

keep up backwards compatibility, while switching to ``XMLSyntaxError`` as an

interface.

4.5.2 (2020-07-09)

==================

Bugs fixed

----------

* ``Cleaner()`` now validates that only known configuration options can be set.

* LP#1882606: ``Cleaner.clean_html()`` discarded comments and PIs regardless of the

corresponding configuration option, if ``remove_unknown_tags`` was set.

* LP#1880251: Instead of globally overwriting the document loader in libxml2, lxml now

sets it per parser run, which improves the interoperability with other users of libxml2

such as libxmlsec.

* LP#1881960: Fix build in CPython 3.10 by using Cython 0.29.21.

* The setup options "--with-xml2-config" and "--with-xslt-config" were accidentally renamed

to "--xml2-config" and "--xslt-config" in 4.5.1 and are now available again.

4.5.1 (2020-05-19)

==================

Bugs fixed

----------

* LP#1570388: Fix failures when serialising documents larger than 2GB in some cases.

* LP#1865141, GH#298: ``QName`` values were not accepted by the ``el.iter()`` method.

Patch by xmo-odoo.

* LP#1863413, GH#297: The build failed to detect libraries on Linux that are only

configured via pkg-config.

Patch by Hugh McMaster.

4.5.0 (2020-01-29)

==================

Features added

--------------

* A new function ``indent()`` was added to insert tail whitespace for pretty-printing

an XML tree.

Bugs fixed

----------

* LP#1857794: Tail text of nodes that get removed from a document using item

deletion disappeared silently instead of sticking with the node that was removed.

Other changes

-------------

* MacOS builds are 64-bit-only by default.

Set CFLAGS and LDFLAGS explicitly to override it.

* Linux/MacOS Binary wheels now use libxml2 2.9.10 and libxslt 1.1.34.

* LP#1840234: The package version number is now available as ``lxml.__version__``.

4.4.3 (2020-01-28)

==================

Bugs fixed

----------

* LP#1844674: ``itertext()`` was missing tail text of comments and PIs since 4.4.0.

4.4.2 (2019-11-25)

==================

Bugs fixed

----------