CVE-2026-31958

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Source
https://cve.org/CVERecord?id=CVE-2026-31958
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31958.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-31958
Aliases
Downstream
Related
Published
2026-03-11T19:27:23.380Z
Modified
2026-03-25T17:44:19.358877Z
Severity
  • 8.7 (High) CVSS_V4 - 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 CVSS Calculator
Summary
Tornado has a DoS due to too many multipart parts
Details

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 maxbodysize 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.

Database specific 
{
    "cwe_ids": [
        "CWE-400"
    ],
    "cna_assigner": "GitHub_M",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31958.json"
}
References

Affected packages

Git / github.com/tornadoweb/tornado

Affected ranges

Type
GIT
Repo
https://github.com/tornadoweb/tornado
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
7d6465056ceb7a054b3f64cf1c18271753b10482
Database specific 
{
    "versions": [
        {
            "introduced": "0"
        },
        {
            "fixed": "6.5.5"
        }
    ]
}

Affected versions

v1.*
v1.0.0
v1.1.0
v1.1.1
v1.2.0
v1.2.1
v2.*
v2.0.0
v2.1.0
v2.1.1
v2.2.0
v2.2.1
v2.3.0
v2.4.0
v2.4.1
v3.*
v3.0.0
v3.0.1
v3.0.2
v3.1.0
v3.1.1
v3.2.0
v3.2.0b1
v3.2.0b2
v3.2.1
v3.2.2
v4.*
v4.0.0
v4.0.0b1
v4.0.0b2
v4.0.0b3
v4.0.1
v4.0.2
v4.1.0
v4.1.0b1
v4.1.0b2
v4.2.0
v4.2.0b1
v4.2.1
v4.3.0
v4.3.0b1
v4.3.0b2
v4.4.0
v4.4.0b1
v4.4.1
v4.4.2
v4.4.3
v4.5.0
v4.5.1
v4.5.2
v4.5.3
v5.*
v5.0.0
v5.0.1
v5.1.0
v5.1.0b1
v6.*
v6.0.0
v6.0.0b1
v6.1.0
v6.1.0b1
v6.1.0b2
v6.2.0
v6.2.0b1
v6.2.0b2
v6.3.0
v6.3.0b1
v6.3.1
v6.4.0
v6.4.0b1
v6.4.1
v6.5.0
v6.5.0b1
v6.5.1
v6.5.2
v6.5.3
v6.5.4

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31958.json"