CVE-2026-31958
HIGH EPSS 29.3%
Published Mar 11, 20263mo ago · Modified Jun 17, 20262w ago
8.7 CVSS 4.0
Published Mar 11, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago
Description
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
29.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-400 Uncontrolled Resource Consumption Resource Mgmt
Affected Products 1
| Vendor | Product | Version | Range |
|---|---|---|---|
| tornadoweb | tornado | * | <6.5.5 |
References 2
- github.com https://github.com/tornadoweb/tornado/security/advisories/GHSA-qjxf-f2mg-c6mc
- lists.debian.org https://lists.debian.org/debian-lts-announce/2026/04/msg00000.html
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.