{"id":"UBUNTU-CVE-2026-86410","details":"A flaw in the curl command line tool's logic makes it only set SSH host verification options when interacting directly using SFTP or SCP, and not as a result of following a redirect. This means `--knownhosts`, `--hostpubsha256`, and `--hostpubmd5` are never installed when the initial URL is HTTPS. If `--location` and `--proto-redir +sftp` is used and the server returns a `Location: sftp://example.com` redirect, the SFTP connection proceeds without any of the user's requested SSH host verification methods.","modified":"2026-10-17T13:01:13.946091477Z","published":"2026-10-14T06:00:00Z","related":["USN-8927-1"],"upstream":["CVE-2026-86410"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-86410"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-86410"},{"type":"REPORT","url":"https://curl.se/docs/CVE-2026-86410.html"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8927-1"}],"affected":[{"package":{"name":"curl","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/curl?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["8.18.0-1ubuntu2","8.20.0-2ubuntu1","8.20.0-2ubuntu3","8.20.0-2ubuntu10","8.20.0-2ubuntu11"],"ecosystem_specific":{"priority_reason":"Upstream defined this as low severity","binaries":[{"binary_version":"8.20.0-2ubuntu11","binary_name":"curl"},{"binary_name":"libcurl3t64-gnutls","binary_version":"8.20.0-2ubuntu11"},{"binary_name":"libcurl4t64","binary_version":"8.20.0-2ubuntu11"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86410.json"}},{"package":{"name":"curl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/curl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"8.18.0-1ubuntu2.8"}]}],"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","8.18.0-1ubuntu2.7"],"ecosystem_specific":{"availability":"No subscription required","priority_reason":"Upstream defined this as low severity","binaries":[{"binary_version":"8.18.0-1ubuntu2.8","binary_name":"curl"},{"binary_name":"libcurl3t64-gnutls","binary_version":"8.18.0-1ubuntu2.8"},{"binary_name":"libcurl4t64","binary_version":"8.18.0-1ubuntu2.8"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86410.json"}}],"schema_version":"1.9.0","severity":[{"type":"Ubuntu","score":"low"}]}