PyPI/tornado CVE-2026-91990: medium, EPSS 0.42%

tornado: multipart split() creates huge temp list before max_parts check -> memory amplification DoS (httputil.py:34)

Action: Upgrade tornado to 6.5.8 or later.

pip install tornado==6.5.8

Affected

Fixed versions

Sources

• osv: GHSA-8423-8fgw-73vq
• https://github.com/tornadoweb/tornado/security/advisories/GHSA-8423-8fgw-73vq
• https://github.com/tornadoweb/tornado/pull/3704
• https://github.com/tornadoweb/tornado/commit/de85b3f87446e323e881bbaa3d5a74f4b76e5f05
• https://gist.github.com/afldl/649861f25d39b53b7edbe0298e171617
• https://github.com/tornadoweb/tornado
• https://github.com/tornadoweb/tornado/releases/tag/v6.5.8

CVE-2026-91990 · published 2026-09-01T20:17:38Z · modified 2026-09-16T03:56:01.992806508Z · JSON