CVE-2025-6069 (GCVE-0-2025-6069)

Vulnerability from cvelistv5 – Published: 2025-06-17 13:39 – Updated: 2026-04-21 20:17
VLAI
Title
HTMLParser quadratic complexity when processing malformed inputs
Summary
The html.parser.HTMLParser class had worse-case quadratic complexity when processing certain crafted malformed inputs potentially leading to amplified denial-of-service.
Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
PSF
References
Impacted products
Vendor Product Version
Python Software Foundation CPython Affected: 0 , < 3.10.19 (python)
Affected: 3.11.0 , < 3.11.14 (python)
Affected: 3.12.0 , < 3.12.12 (python)
Affected: 3.13.0 , < 3.13.6 (python)
Affected: 3.14.0a1 , < 3.14.0b3 (python)
Create a notification for this product.
Credits
Serhiy Storchaka Jake Howard sw0rd1ight
Show details on NVD website
To clipboard 

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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.
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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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