CVE-2026-3276 (GCVE-0-2026-3276)

Vulnerability from cvelistv5 – Published: 2026-06-03 14:29 – Updated: 2026-06-16 14:54
VLAI?
Title
Potential DoS via quadratic complexity in unicodedata.normalize()
Summary
unicodedata.normalize() can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.13.14 (python)
Affected: 3.14.0 , < 3.14.6 (python)
Affected: 3.15.0a1 , < 3.15.0b2 (python)
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Credits
Seokchan Yoon (https://github.com/ch4n3-yoon) Tim Peters (https://github.com/tim-one) Bénédikt Tran (https://github.com/picnixz) Serhiy Storchaka (https://github.com/serhiy-storchaka) Stan Ulbrych (https://github.com/StanFromIreland) Seth Larson (https://github.com/sethmlarson) Petr Viktorin (https://github.com/encukou)
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  • 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.
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  • 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.



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