{"id":"UBUNTU-CVE-2026-54283","details":"Starlette is a lightweight ASGI framework/toolkit. From 0.4.1 until 1.3.1, request.form() accepts max_fields and max_part_size to bound resource consumption while parsing form data. These limits are enforced for multipart/form-data, but silently ignored for application/x-www-form-urlencoded. An unauthenticated attacker can therefore send a urlencoded body with an arbitrarily large number of fields or an arbitrarily large field, even when the application configured limits it believed would apply. This vulnerability is fixed in 1.3.1.","modified":"2026-06-24T11:01:53.859862257Z","published":"2026-06-22T18:16:00Z","upstream":["CVE-2026-54283"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-54283"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-54283"},{"type":"REPORT","url":"https://github.com/Kludex/starlette/security/advisories/GHSA-82w8-qh3p-5jfq"},{"type":"REPORT","url":"https://github.com/Kludex/starlette/pull/3329"}],"affected":[{"package":{"name":"starlette","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/starlette?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.14.1-1","0.16.0-1","0.18.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-starlette","binary_version":"0.18.0-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54283.json"}},{"package":{"name":"starlette","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/starlette?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.30.0-1","0.31.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.31.1-1","binary_name":"python3-starlette"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54283.json"}},{"package":{"name":"starlette","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/starlette?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.46.1-2","0.46.1-3"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-starlette","binary_version":"0.46.1-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54283.json"}},{"package":{"name":"starlette","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/starlette?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.46.1-3","0.50.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.50.0-1","binary_name":"python3-starlette"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54283.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}