{"id":"UBUNTU-CVE-2026-121727","details":"Kore before 4.3.0 contains an integer underflow vulnerability in HTTP request body handling that allows unauthenticated attackers to bypass http_body_max by sending more body bytes than declared. Attackers can send oversized first segments over many concurrent POST, PUT or DELETE connections, wrapping content_length to grow buffers unbounded and exhaust worker memory.","modified":"2026-11-05T11:46:32.359570053Z","published":"2026-11-03T23:17:00Z","upstream":["CVE-2026-121727"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-121727"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-121727"},{"type":"REPORT","url":"https://github.com/jorisvink/kore"},{"type":"REPORT","url":"https://github.com/jorisvink/kore/blob/4.3.0-rc5/src/http.c#L934"},{"type":"REPORT","url":"https://github.com/jorisvink/kore/commit/1ff3c0f6f7973dc7fc8bf38369790ef2d8079b3b"},{"type":"REPORT","url":"https://kore.io/releases/4.3.0"},{"type":"REPORT","url":"https://www.vulncheck.com/advisories/kore-before-4.3.0-integer-underflow-memory-exhaustion-via-http-header-recv"}],"affected":[{"package":{"name":"kore","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/kore?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.2.3-1","1.2.3-2","1.2.3-3","1.2.3-4","1.2.3-5"],"ecosystem_specific":{"binaries":[{"binary_name":"kore","binary_version":"1.2.3-5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}},{"package":{"name":"kore","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/kore?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.0-4","3.3.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.3.1-1","binary_name":"kore"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}},{"package":{"name":"kore","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/kore?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.0-3","4.1.0-4","4.1.0-4ubuntu1","4.1.0-6"],"ecosystem_specific":{"binaries":[{"binary_name":"kore","binary_version":"4.1.0-6"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}},{"package":{"name":"kore","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/kore?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.0-6"],"ecosystem_specific":{"binaries":[{"binary_version":"4.1.0-6","binary_name":"kore"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}},{"package":{"name":"kore","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/kore?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.3-2","4.2.3-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"kore","binary_version":"4.2.3-2build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}},{"package":{"name":"kore","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/kore?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.3-2"],"ecosystem_specific":{"binaries":[{"binary_version":"4.2.3-2","binary_name":"kore"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-121727.json"}}],"schema_version":"1.9.2","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":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}