CVE-2026-25673 (GCVE-0-2026-25673)

Vulnerability from cvelistv5 – Published: 2026-03-03 14:28 – Updated: 2026-03-03 15:26
VLAI
Title
Potential denial-of-service vulnerability in URLField via Unicode normalization on Windows
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
DSF
References
Impacted products
Vendor Product Version
djangoproject Django Affected: 6.0 , < 6.0.3 (semver)
Unaffected: 6.0.3 (semver)
Affected: 5.2 , < 5.2.12 (semver)
Unaffected: 5.2.12 (semver)
Affected: 4.2 , < 4.2.29 (semver)
Unaffected: 4.2.29 (semver)
Create a notification for this product.
Date Public
2026-03-03 08:00
Credits
Seokchan Yoon Natalia Bidart Natalia Bidart
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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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.
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  • 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.