Vulnerability-Lookup

GHSA-77QW-3XM6-R2PP

Vulnerability from github – Published: 2026-07-28 15:32 – Updated: 2026-07-28 18:33

Details

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.

Severity

2.0 (Low)


                  
                    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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-6879"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-407"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T15:17:51Z",
    "severity": "LOW"
  },
  "details": "`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\u00a0 of the sibling list, such as with `[last()]` or `[last()-N]`;\u00a0 `.//item[1]` short-circuits after the first match.",
  "id": "GHSA-77qw-3xm6-r2pp",
  "modified": "2026-07-28T18:33:02Z",
  "published": "2026-07-28T15:32:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6879"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/issues/152674"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/pull/152676"
    },
    {
      "type": "WEB",
      "url": "https://github.com/python/cpython/commit/2ffab083782968a4d732738f4f1dff6bbd69d2b0"
    },
    {
      "type": "WEB",
      "url": "https://mail.python.org/archives/list/security-announce@python.org/thread/7YMZ6DDZVR26TJJBVO3RDNBAVGHNYAKR"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-6879 (GCVE-0-2026-6879)

Vulnerability from cvelistv5 – Published: 2026-07-28 13:46 – Updated: 2026-07-28 14:54

Title

Quadratic Behavior in xml.etree.ElementPath Index Predicates

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.

Severity

2 (Low)


                        
                          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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-407 - Inefficient Algorithmic Complexity

Assigner

PSF

References

4 references

URL	Tags
https://github.com/python/cpython/pull/152676	patch
https://github.com/python/cpython/issues/152674	issue-tracking
https://mail.python.org/archives/list/security-an…	vendor-advisory
https://github.com/python/cpython/commit/2ffab083…	patch

Impacted products

1 product

Vendor	Product	Version
Python Software Foundation	CPython	Affected: 0 , < 3.15.0 (python)

Credits

dm (https://github.com/DarkaMaul) Petr Viktorin (https://github.com/encukou)

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                  },
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                "timestamp": "2026-07-28T14:49:33.309576Z",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

GHSA-77QW-3XM6-R2PP

CVE-2026-6879 (GCVE-0-2026-6879)

Tags

Sightings

Nomenclature