CVE-2026-6879

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems. New built-in modules are easily written in C or C++ (or other languages, depending on the chosen implementation). Python is also usable as an extension language for applications written in other languages that need easy-to-use scripting or automation interfaces.

Security Fix(es):

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.(CVE-2026-6879)

Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems. New built-in modules are easily written in C or C++ (or other languages, depending on the chosen implementation). Python is also usable as an extension language for applications written in other languages that need easy-to-use scripting or automation interfaces.

Security Fix(es):

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.(CVE-2026-6879)

Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems. New built-in modules are easily written in C or C++ (or other languages, depending on the chosen implementation). Python is also usable as an extension language for applications written in other languages that need easy-to-use scripting or automation interfaces.

Security Fix(es):

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.(CVE-2026-6879)

xml.parsers.expat and xml.etree.ElementTree use insufficient entropy for Expat hash-flooding protection, which allows a crafted XML document to trigger hash flooding. Fully mitigating this vulnerability requires both updating libexpat to 2.8.0 or later and applying this patch.(CVE-2026-7210)

Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems. New built-in modules are easily written in C or C++ (or other languages, depending on the chosen implementation). Python is also usable as an extension language for applications written in other languages that need easy-to-use scripting or automation interfaces.

Security Fix(es):

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.(CVE-2026-6879)

Python combines remarkable power with very clear syntax. It has modules, classes, exceptions, very high level dynamic data types, and dynamic typing. There are interfaces to many system calls and libraries, as well as to various windowing systems. New built-in modules are easily written in C or C++ (or other languages, depending on the chosen implementation). Python is also usable as an extension language for applications written in other languages that need easy-to-use scripting or automation interfaces.

Security Fix(es):

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.(CVE-2026-6879)

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

• CVE-2026-6879: xml.etree.ElementPath: avoid quadratic behaviour in XPath index predicates ([1], [last()], [last()-N])
• CVE-2026-18503: fix quadratic time in csv.Sniffer for quoted fields
• Backport upstream 3.11 fixes the CVE-2026-18503 fix relies on or completes: correct matching of possessive quantifiers in the re engine (gh-106052, gh-100061) and super-linear doublequote detection in csv.Sniffer (gh-109638)

These are all security issues fixed in the python315-3.15.0~rc2-1.1 package on the GA media of openSUSE Tumbleweed.

These are all security issues fixed in the python313-3.13.15-1.1 package on the GA media of openSUSE Tumbleweed.

Element.findall() and fully-consumed Element.iterfind() exhibit O(n^2) time complexity when using XPath index predicates (e.g. [1], [last()], [last()-N]) on XML documents with many same-tag siblings. Element.find() is only affected when the first match is near the end  of the sibling list, such as with [last()] or [last()-N];  .//item[1] short-circuits after the first match.

This update for python313 fixes the following issues:

Security issues fixed:

• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-17084: [Security-announce][] StringPrep algorithm considered (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).

Non security issue fixed:

• Conflicts between different versions of Python (bsc#1258364).
• Updated to version 3.13.15

This update for python fixes the following issues:

• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223).
• CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).
• CVE-2026-19672: The tarfile module's tar and data extraction filters created directories outside the destination for members whose name leaves the destination and retu (bsc#1276227).

Changes for python:

• Update bundled setuptools wheels to setuptools-40.6.2-py2.py3-none-any.whl (bsc#1276903)

This update for python fixes the following issues:

• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223).
• CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).
• CVE-2026-19672: The tarfile module's tar and data extraction filters created directories outside the destination for members whose name leaves the destination and retu (bsc#1276227).

Changes for python:

• Update bundled setuptools wheels to setuptools-40.6.2-py2.py3-none-any.whl (bsc#1276903)

This update for python36 fixes the following issues:

Security issues fixed:

• CVE-2026-1703: files may be extracted outside the installation directory when installing and extracting maliciously crafted wheel archives (bsc#1274743).
• CVE-2026-3219: pip doesn't reject concatenated ZIP (bsc#1262429).
• CVE-2026-3446: Base64 decoding stops at first padded quad by default (bsc#1261970).
• CVE-2026-3479: python: improper resource argument validation can allow path traversal (bsc#1259989).
• CVE-2026-4224: C stack overflow when parsing XML with deeply nested DTD content models (bsc#1259735).
• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-13346: Arbitrary file installation via malicious package indexes (bsc#1273090 bsc#1273091 bsc#1273094).
• CVE-2026-15310: memory exhaustion in zipfile in bzip2/LZMA/Zstandard decompression (bsc#1277111).
• CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223).
• CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).
• CVE-2026-19672: tarfile extraction filter bypass allows creation of directories outside the destination (bsc#1276227).
• CVE-2026-82049: tarfile extraction filters mishandle archives containing a hard link to a symbolic link, allowing file modification and content disclosure (bsc#1280459).

Non security issue fixed:

• Update bundled setuptools wheels to setuptools-44.1.1-py2.py3-none-any.whl (bsc#1277271)

This update for python3, python3-base, python3-doc fixes the following issues:

Security issues fixed:

• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-15310: memory exhaustion in zipfile in bzip2/LZMA/Zstandard decompression (bsc#1277111).
• CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223).
• CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).
• CVE-2026-19672: tarfile extraction filter bypass allows creation of directories outside the destination (bsc#1276227).
• CVE-2026-82049: tarfile extraction filters mishandle archives containing a hard link to a symbolic link, allowing file modification and content disclosure (bsc#1280459).

Changes for python3:

• Update bundled setuptools wheels to setuptools-40.6.2 (bsc#1276903).

This update for python3 fixes the following issues:

Security issues fixed:

• CVE-2026-0864: improper handling of line-ending characters can lead to configuration file injection when the configparser module is used (bsc#1269066).
• CVE-2026-1703: files may be extracted outside the installation directory when installing and extracting maliciously crafted wheel archives (bsc#1257599 bsc#1274743).
• CVE-2026-3219: pip doesn't reject concatenated ZIP (bsc#1262429 bsc#1262467).
• CVE-2026-3276: quadratic complexity in unicodedata.normalize() can lead to DoS when processing specially crafted Unicode input (bsc#1267581).
• CVE-2026-3446: Base64 decoding stops at first padded quad by default (bsc#1261970).
• CVE-2026-3479: python: improper resource argument validation can allow path traversal (bsc#1259989).
• CVE-2026-4224: C stack overflow when parsing XML with deeply nested DTD content models (bsc#1259735).
• CVE-2026-4360: in the Tarfile.extract() function, the filter parameter is not passed properly when extracting hardlinks (bsc#1269959).
• CVE-2026-6357: pip self-update functionality can import newly installed modules after wheel installation (bsc#1263442 bsc#1263443).
• CVE-2026-6879: quadratic behavior in xml.etree.ElementPath index predicates can lead to a denial of service via high CPU usage (bsc#1273148).
• CVE-2026-7210: xml.parsers.expat and xml.etree.ElementTree use insufficient entropy for Expat hash-flooding protection (bsc#1264962).
• CVE-2026-7774: tarfile.data_filter path traversal bypass allows writing outside the extraction directory (bsc#1267821).
• CVE-2026-8328: ftpcp() does not use actual peer address and trusts server-supplied PASV host address (bsc#1265268).
• CVE-2026-8643: Path traversal via malicious entry point name in pip wheel installation allows arbitrary file overwrite (bsc#1266669).
• CVE-2026-9669: crafted input can cause a stack buffer overflow (bsc#1267974).
• CVE-2026-11940: tarfile extraction filter bypass via a crafted archive allows escaping the destination directory and enables arbitrary file reads and writes (bsc#1268977).
• CVE-2026-11972: infinite loop due to improper EOF handling in the tarfile module streaming mode can lead to DoS (bsc#1269788).
• CVE-2026-13346: Arbitrary file installation via malicious package indexes (bsc#1273090 bsc#1273091 bsc#1273094).
• CVE-2026-15308: Incremental HTMLParser allows CPU-exhaustion DoS via repeated unterminated markup declarations (bsc#1271192).
• CVE-2026-15310: memory exhaustion in zipfile in bzip2/LZMA/Zstandard decompression (bsc#1277111).
• CVE-2026-15806: urllib.request.HTTPPasswordMgr credentials for one URL scheme sent over another scheme (bsc#1276223).
• CVE-2026-17084: StringPrep algorithm considered Unicode codepoint attributes outside Unicode 3.2.0 (bsc#1276226).
• CVE-2026-18503: attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU (bsc#1274683).
• CVE-2026-19672: tarfile extraction filter bypass allows creation of directories outside the destination (bsc#1276227).
• CVE-2026-82049: tarfile extraction filters mishandle archives containing a hard link to a symbolic link, allowing file modification and content disclosure (bsc#1280459).

Non security issue fixed:

• Fix an error that returned non-zero exit status 1 (bsc#1277271).
• Fix regression in http.cookies (bsc#1263083).
• Update bundled pip wheels to pip-20.0.2-py2.py3-none-any.whl.