{"id":"UBUNTU-CVE-2026-40347","details":"Python-Multipart is a streaming multipart parser for Python. Versions prior to 0.0.26 have a denial of service vulnerability when parsing crafted `multipart/form-data` requests with large preamble or epilogue sections. Upgrade to version 0.0.26 or later, which skips ahead to the next boundary candidate when processing leading CR/LF data and immediately discards epilogue data after the closing boundary.","modified":"2026-05-20T16:12:58.750691189Z","published":"2026-04-18T00:16:00Z","upstream":["CVE-2026-40347"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-40347"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-40347"},{"type":"REPORT","url":"https://github.com/Kludex/python-multipart/security/advisories/GHSA-mj87-hwqh-73pj"},{"type":"REPORT","url":"https://github.com/Kludex/python-multipart/pull/259"}],"affected":[{"package":{"name":"python-multipart","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/python-multipart?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0.5-2","0.0.5-2ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-multipart","binary_version":"0.0.5-2ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40347.json"}},{"package":{"name":"python-multipart","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/python-multipart?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0.5-3","0.0.6-1","0.0.9-1","0.0.9-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.0.9-1ubuntu0.1~esm1","binary_name":"python3-multipart"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40347.json"}},{"package":{"name":"python-multipart","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/python-multipart?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0.20-1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.0.20-1","binary_name":"python3-python-multipart"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40347.json"}},{"package":{"name":"python-multipart","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/python-multipart?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.0.20-1","0.0.20-1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-python-multipart","binary_version":"0.0.20-1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-40347.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:L"},{"type":"Ubuntu","score":"medium"}]}