{"action":"Upgrade tornado to 6.5.8 or later.","affected":[{"fixed":"6.5.8","introduced":"0"}],"component":"tornado","cve_ids":["CVE-2026-91990"],"ecosystem":"PyPI","epss":0.00424,"exploited":false,"fixed_versions":["6.5.8"],"ghsa_id":"GHSA-8423-8fgw-73vq","id":"tcs_01M5KF75FC2Z6VJMM8Y3T6VPZH","modified_at":"2026-09-16T03:56:01.992806508Z","published_at":"2026-09-01T20:17:38Z","references":["https://osv.dev/vulnerability/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"],"severity":{"label":"medium"},"sources":[{"source":"osv","source_id":"GHSA-8423-8fgw-73vq","url":"https://osv.dev/vulnerability/GHSA-8423-8fgw-73vq"}],"summary":"tornado: multipart split() creates huge temp list before max_parts check -> memory amplification DoS (httputil.py:34)"}