{"id":"UBUNTU-CVE-2026-19931","details":"A flaw in libcurl makes it wrongly reuse an HTTP connection setup for a given hostname using Negotiate authentication, when the initial request is done using empty credentials. This can make user B's request get sent over user A's previously authenticated connection.","modified":"2026-09-16T11:31:18Z","published":"2026-09-06T18:17:00Z","upstream":["CVE-2026-19931"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-19931"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-19931"},{"type":"REPORT","url":"https://curl.se/docs/CVE-2026-19931.html"},{"type":"REPORT","url":"https://github.com/curl/curl/commit/7103a93b05bc69ea98ed9d"}],"affected":[{"package":{"name":"curl","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/curl?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.65.3-1ubuntu3","7.65.3-1ubuntu4","7.66.0-1ubuntu1","7.67.0-2ubuntu1","7.68.0-1ubuntu1","7.68.0-1ubuntu2","7.68.0-1ubuntu2.1","7.68.0-1ubuntu2.2","7.68.0-1ubuntu2.4","7.68.0-1ubuntu2.5","7.68.0-1ubuntu2.6","7.68.0-1ubuntu2.7","7.68.0-1ubuntu2.10","7.68.0-1ubuntu2.11","7.68.0-1ubuntu2.12","7.68.0-1ubuntu2.13","7.68.0-1ubuntu2.14","7.68.0-1ubuntu2.15","7.68.0-1ubuntu2.16","7.68.0-1ubuntu2.18","7.68.0-1ubuntu2.19","7.68.0-1ubuntu2.20","7.68.0-1ubuntu2.21","7.68.0-1ubuntu2.22","7.68.0-1ubuntu2.23","7.68.0-1ubuntu2.24","7.68.0-1ubuntu2.25","7.68.0-1ubuntu2.25+esm2","7.68.0-1ubuntu2.25+esm3","7.68.0-1ubuntu2.25+esm4","7.68.0-1ubuntu2.25+esm5","7.68.0-1ubuntu2.25+esm6","7.68.0-1ubuntu2.25+esm7"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"7.68.0-1ubuntu2.25+esm7"},{"binary_name":"libcurl3-gnutls","binary_version":"7.68.0-1ubuntu2.25+esm7"},{"binary_version":"7.68.0-1ubuntu2.25+esm7","binary_name":"libcurl3-nss"},{"binary_version":"7.68.0-1ubuntu2.25+esm7","binary_name":"libcurl4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-19931.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/curl?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.74.0-1.3ubuntu2","7.74.0-1.3ubuntu3","7.80.0-3","7.81.0-1","7.81.0-1ubuntu1.1","7.81.0-1ubuntu1.2","7.81.0-1ubuntu1.3","7.81.0-1ubuntu1.4","7.81.0-1ubuntu1.6","7.81.0-1ubuntu1.7","7.81.0-1ubuntu1.8","7.81.0-1ubuntu1.10","7.81.0-1ubuntu1.11","7.81.0-1ubuntu1.13","7.81.0-1ubuntu1.14","7.81.0-1ubuntu1.15","7.81.0-1ubuntu1.16","7.81.0-1ubuntu1.17","7.81.0-1ubuntu1.18","7.81.0-1ubuntu1.19","7.81.0-1ubuntu1.20","7.81.0-1ubuntu1.21","7.81.0-1ubuntu1.22","7.81.0-1ubuntu1.23","7.81.0-1ubuntu1.24","7.81.0-1ubuntu1.25","7.81.0-1ubuntu1.26","7.81.0-1ubuntu1.27"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"7.81.0-1ubuntu1.27"},{"binary_version":"7.81.0-1ubuntu1.27","binary_name":"libcurl3-gnutls"},{"binary_name":"libcurl3-nss","binary_version":"7.81.0-1ubuntu1.27"},{"binary_version":"7.81.0-1ubuntu1.27","binary_name":"libcurl4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-19931.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/curl?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.2.1-1ubuntu3","8.2.1-1ubuntu3.1","8.4.0-2ubuntu1","8.5.0-2ubuntu1","8.5.0-2ubuntu2","8.5.0-2ubuntu8","8.5.0-2ubuntu9","8.5.0-2ubuntu10","8.5.0-2ubuntu10.1","8.5.0-2ubuntu10.2","8.5.0-2ubuntu10.3","8.5.0-2ubuntu10.4","8.5.0-2ubuntu10.5","8.5.0-2ubuntu10.6","8.5.0-2ubuntu10.7","8.5.0-2ubuntu10.8","8.5.0-2ubuntu10.9","8.5.0-2ubuntu10.10","8.5.0-2ubuntu10.11","8.5.0-2ubuntu10.12","8.5.0-2ubuntu10.13"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"8.5.0-2ubuntu10.13"},{"binary_version":"8.5.0-2ubuntu10.13","binary_name":"libcurl3t64-gnutls"},{"binary_name":"libcurl4t64","binary_version":"8.5.0-2ubuntu10.13"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-19931.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/curl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.14.1-2ubuntu1","8.17.0-1ubuntu1","8.18.0-1ubuntu1","8.18.0-1ubuntu2","8.18.0-1ubuntu2.1","8.18.0-1ubuntu2.2","8.18.0-1ubuntu2.3","8.18.0-1ubuntu2.4","8.18.0-1ubuntu2.5"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"8.18.0-1ubuntu2.5"},{"binary_name":"libcurl3t64-gnutls","binary_version":"8.18.0-1ubuntu2.5"},{"binary_name":"libcurl4t64","binary_version":"8.18.0-1ubuntu2.5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-19931.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}