CVE-2026-91990

Tornado before 6.5.8 contains a memory amplification vulnerability in parse_multipart_form_data that splits multipart data before validating the max_parts limit. Attackers can send crafted multipart requests with many parts to create large transient lists, exhausting server memory and causing denial of service.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tornadoweb/tornado/security/advisories/GHSA-8423-8fgw-73vq
https://www.vulncheck.com/advisories/tornado-before-6.5.8-memory-amplification-dos-via-multipart
https://github.com/tornadoweb/tornado/security/advisories/GHSA-8423-8fgw-73vq

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 16:17

Updated : 2026-09-16 13:42

NVD link : CVE-2026-91990

Mitre link : CVE-2026-91990

CVE.ORG link : CVE-2026-91990

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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