CVE-2026-31958 (GCVE-0-2026-31958)
Vulnerability from cvelistv5
Published
2026-03-11 19:27
Modified
2026-04-01 14:32
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Summary
Tornado is a Python web framework and asynchronous networking library. In versions of Tornado prior to 6.5.5, the only limit on the number of parts in multipart/form-data is the max_body_size setting (default 100MB). Since parsing occurs synchronously on the main thread, this creates the possibility of denial-of-service due to the cost of parsing very large multipart bodies with many parts. This vulnerability is fixed in 6.5.5.
References
Impacted products
Vendor Product Version
tornadoweb tornado Version: < 6.5.5
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