{"id":"UBUNTU-CVE-2026-3784","details":"curl would wrongly reuse an existing HTTP proxy connection doing CONNECT to a server, even if the new request uses different credentials for the HTTP proxy. The proper behavior is to create or use a separate connection.","modified":"2026-03-19T08:49:09.042273Z","published":"2026-03-11T18:00:00Z","related":["USN-8084-1","USN-8099-1"],"upstream":["CVE-2026-3784"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-3784"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-3784"},{"type":"REPORT","url":"https://curl.se/docs/CVE-2026-3784.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8084-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8099-1"}],"affected":[{"package":{"name":"curl","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/curl@7.58.0-2ubuntu3.24+esm8?arch=source&distro=esm-infra/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.58.0-2ubuntu3.24+esm8"}]}],"versions":["7.55.1-1ubuntu2","7.55.1-1ubuntu2.1","7.57.0-1ubuntu1","7.58.0-2ubuntu1","7.58.0-2ubuntu2","7.58.0-2ubuntu3","7.58.0-2ubuntu3.1","7.58.0-2ubuntu3.2","7.58.0-2ubuntu3.3","7.58.0-2ubuntu3.5","7.58.0-2ubuntu3.6","7.58.0-2ubuntu3.7","7.58.0-2ubuntu3.8","7.58.0-2ubuntu3.9","7.58.0-2ubuntu3.10","7.58.0-2ubuntu3.12","7.58.0-2ubuntu3.13","7.58.0-2ubuntu3.14","7.58.0-2ubuntu3.15","7.58.0-2ubuntu3.16","7.58.0-2ubuntu3.17","7.58.0-2ubuntu3.18","7.58.0-2ubuntu3.19","7.58.0-2ubuntu3.20","7.58.0-2ubuntu3.21","7.58.0-2ubuntu3.22","7.58.0-2ubuntu3.23","7.58.0-2ubuntu3.24","7.58.0-2ubuntu3.24+esm1","7.58.0-2ubuntu3.24+esm2","7.58.0-2ubuntu3.24+esm3","7.58.0-2ubuntu3.24+esm4","7.58.0-2ubuntu3.24+esm5","7.58.0-2ubuntu3.24+esm7"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl3-gnutls","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl3-nss","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl4","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl4-gnutls-dev","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl4-nss-dev","binary_version":"7.58.0-2ubuntu3.24+esm8"},{"binary_name":"libcurl4-openssl-dev","binary_version":"7.58.0-2ubuntu3.24+esm8"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","priority_reason":"Upstream defined it as 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with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","priority_reason":"Upstream defined it as 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subscription required","priority_reason":"Upstream defined it as low"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-3784.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/curl@8.5.0-2ubuntu10.8?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.5.0-2ubuntu10.8"}]}],"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"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"8.5.0-2ubuntu10.8"},{"binary_name":"libcurl3t64-gnutls","binary_version":"8.5.0-2ubuntu10.8"},{"binary_name":"libcurl4-gnutls-dev","binary_version":"8.5.0-2ubuntu10.8"},{"binary_name":"libcurl4-openssl-dev","binary_version":"8.5.0-2ubuntu10.8"},{"binary_name":"libcurl4t64","binary_version":"8.5.0-2ubuntu10.8"}],"availability":"No subscription required","priority_reason":"Upstream defined it as low"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-3784.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/curl@8.14.1-2ubuntu1.2?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.14.1-2ubuntu1.2"}]}],"versions":["8.12.1-3ubuntu1","8.13.0-5ubuntu1","8.14.1-1ubuntu2","8.14.1-1ubuntu3","8.14.1-2ubuntu1","8.14.1-2ubuntu1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"curl","binary_version":"8.14.1-2ubuntu1.2"},{"binary_name":"libcurl3t64-gnutls","binary_version":"8.14.1-2ubuntu1.2"},{"binary_name":"libcurl4-gnutls-dev","binary_version":"8.14.1-2ubuntu1.2"},{"binary_name":"libcurl4-openssl-dev","binary_version":"8.14.1-2ubuntu1.2"},{"binary_name":"libcurl4t64","binary_version":"8.14.1-2ubuntu1.2"}],"availability":"No subscription required","priority_reason":"Upstream defined it as low"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-3784.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:L/I:L/A:N"},{"type":"Ubuntu","score":"low"}]}