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CVE-2026-25673

CVE-2026-25673 · Potential denial-of-service vulnerability in URLField via Unicode normalization on Windows

This page contains facts from public vulnerability sources. Check the original advisory before updating.

An issue was discovered in 6.0 before 6.0.3, 5.2 before 5.2.12, and 4.2 before 4.2.29. `URLField.to_python()` in Django calls `urllib.parse.urlsplit()`, which performs NFKC normalization on Windows that is disproportionately slow for certain Unicode characters, allowing a remote attacker to cause denial of service via large URL inputs containing these characters. Earlier, unsupported Django series (such as 5.0.x, 4.1.x, and 3.2.x) were not evaluated and may also be affected. Django would like to thank Seokchan Yoon for reporting this issue.

CVSS 7.5 · High · EPSS 1.2% · Fix available

Published
Updated

Stack: python

Affected products and versions

  • django

    Versions
    • ≥ 6.0, < 6.0.3: Affected (semver)
    • 6.0.3: Not affected (semver)
    • ≥ 5.2, < 5.2.12: Affected (semver)
    • 5.2.12: Not affected (semver)
    • ≥ 4.2, < 4.2.29: Affected (semver)
    • 4.2.29: Not affected (semver)

    Update to 4.2.29; Update to 5.2.12; Update to 6.0.3

  • django PyPI

    Versions
    • 6.0
    • 6.0.1
    • 6.0.2
    Affected ranges
    • ECOSYSTEM: ≥ 6.0, < 6.0.3

    Update to 6.0.3

  • django PyPI

    Versions
    • 5.2
    • 5.2.1
    • 5.2.10
    • 5.2.11
    • 5.2.2
    • 5.2.3
    • 5.2.4
    • 5.2.5
    • 5.2.6
    • 5.2.7
    • 5.2.8
    • 5.2.9
    Affected ranges
    • ECOSYSTEM: ≥ 5.2, < 5.2.12

    Update to 5.2.12

  • django PyPI

    Versions
    • 4.2
    • 4.2.1
    • 4.2.10
    • 4.2.11
    • 4.2.12
    • 4.2.13
    • 4.2.14
    • 4.2.15
    • 4.2.16
    • 4.2.17
    • 4.2.18
    • 4.2.19
    • 4.2.2
    • 4.2.20
    • 4.2.21
    • 4.2.22
    • 4.2.23
    • 4.2.24
    • 4.2.25
    • 4.2.26
    • 4.2.27
    • 4.2.28
    • 4.2.3
    • 4.2.4
    • 4.2.5
    • 4.2.6
    • 4.2.7
    • 4.2.8
    • 4.2.9
    Affected ranges
    • ECOSYSTEM: ≥ 4.2, < 4.2.29

    Update to 4.2.29

  • django PyPI

    Versions
    • 4.2
    • 4.2.1
    • 4.2.10
    • 4.2.11
    • 4.2.12
    • 4.2.13
    • 4.2.14
    • 4.2.15
    • 4.2.16
    • 4.2.17
    • 4.2.18
    • 4.2.19
    • 4.2.2
    • 4.2.20
    • 4.2.21
    • 4.2.22
    • 4.2.23
    • 4.2.24
    • 4.2.25
    • 4.2.26
    • 4.2.27
    • 4.2.28
    • 4.2.3
    • 4.2.4
    • 4.2.5
    • 4.2.6
    • 4.2.7
    • 4.2.8
    • 4.2.9
    • 5.2
    • 5.2.1
    • 5.2.10
    • 5.2.11
    • 5.2.2
    • 5.2.3
    • 5.2.4
    • 5.2.5
    • 5.2.6
    • 5.2.7
    • 5.2.8
    • 5.2.9
    • 6.0
    • 6.0.1
    • 6.0.2
    Affected ranges
    • ECOSYSTEM: ≥ 4.2, < 4.2.29 ∪ ≥ 5.2, < 5.2.12 ∪ ≥ 6.0, < 6.0.3

    Update to 4.2.29; Update to 5.2.12; Update to 6.0.3

Original sources

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