CVE-2026-6879
2
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Summary
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.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| Python Software Foundation | CPython | 0 < 3.10.21 | affected |
| Python Software Foundation | CPython | 3.11.0 < 3.11.16 | affected |
| Python Software Foundation | CPython | 3.12.0 < 3.12.14 | affected |
| Python Software Foundation | CPython | 3.13.0 < 3.13.15 | affected |
| Python Software Foundation | CPython | 3.14.0 < 3.14.7 | affected |
| Python Software Foundation | CPython | 3.15.0a1 < 3.15.0rc1 | affected |
Weaknesses
ADP Enrichment
CISA ADP Vulnrichment
- SSVC:
- Exploitation: none
- Automatable: no
- Technical Impact: partial
References
- https://github.com/python/cpython/pull/152676
- https://github.com/python/cpython/issues/152674
- https://mail.python.org/archives/list/security-announce@python.org/thread/7YMZ6DDZVR26TJJBVO3RDNBAVGHNYAKR/
- https://github.com/python/cpython/commit/2ffab083782968a4d732738f4f1dff6bbd69d2b0
- https://github.com/python/cpython/commit/02c08e6b747ac43d0d866a4ffa916bedf3423f81
- https://github.com/python/cpython/commit/390337b8ba1658833fdef379e1739c9f9533a8db
- https://github.com/python/cpython/commit/cb409342a19f25656f62e679f8bac265fe1442c3
- https://github.com/python/cpython/commit/96510a3758f4a075f43223afdee3b6ee1a7a7f02
- https://github.com/python/cpython/commit/037965c00a427cba5c05447efadc67c51a492e85
- https://github.com/python/cpython/commit/0583f24ae678993e3f7939f51ad5bcae5ad9dc70
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