{"id":"USN-8799-1","summary":"libssh2 vulnerabilities","details":"It was discovered that libssh2 incorrectly handled certain publickey\nsubsystem attributes. A remote attacker controlling a malicious SSH server\ncould use this issue to cause a denial of service or possibly execute\narbitrary code.\n(CVE-2026-58050)\n\nIt was discovered that libssh2 did not properly initialize publickey list\nentries before parsing. A remote attacker controlling a malicious SSH\nserver could use this issue to cause a denial of service or possibly\nexecute arbitrary code. (CVE-2026-58051)\n\nIt was discovered that libssh2 incorrectly handled certain SFTP server\nresponses. A remote attacker controlling an SSH server could use this issue\nto cause libssh2 to crash or possibly execute arbitrary code.\n(CVE-2026-66032)\n\nIt was discovered that libssh2 did not properly check bounds in certain \npublickey subsystem responses. A remote attacker controlling a malicious \nSSH server could use this issue to cause a denial of service or possibly \nexecute arbitrary code.. (CVE-2026-66034)","modified":"2026-09-23T07:41:41.933830391Z","published":"2026-09-22T03:58:05Z","related":["UBUNTU-CVE-2026-58050","UBUNTU-CVE-2026-58051","UBUNTU-CVE-2026-66032","UBUNTU-CVE-2026-66034"],"upstream":["CVE-2026-58050","CVE-2026-58051","CVE-2026-66032","CVE-2026-66034","UBUNTU-CVE-2026-58050","UBUNTU-CVE-2026-58051","UBUNTU-CVE-2026-66032","UBUNTU-CVE-2026-66034"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8799-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-58050"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-58051"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-66032"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-66034"}],"affected":[{"package":{"name":"libssh2","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libssh2?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.3-2ubuntu0.2+esm4"}]}],"versions":["1.4.3-1","1.4.3-2","1.4.3-2ubuntu0.1","1.4.3-2ubuntu0.2","1.4.3-2ubuntu0.2+esm1","1.4.3-2ubuntu0.2+esm2","1.4.3-2ubuntu0.2+esm3"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro","binaries":[{"binary_version":"1.4.3-2ubuntu0.2+esm4","binary_name":"libssh2-1"}]},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:Pro:14.04:LTS","cves":[{"severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H","type":"CVSS_V3"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"score":"medium","type":"Ubuntu"}],"id":"CVE-2026-58050"},{"severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"score":"medium","type":"Ubuntu"}],"id":"CVE-2026-58051"},{"id":"CVE-2026-66032","severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2026-66034","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"score":"medium","type":"Ubuntu"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8799-1.json"}},{"package":{"name":"libssh2","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/libssh2?arch=source&distro=esm-apps-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.0-2ubuntu0.1+esm3"}]}],"versions":["1.5.0-2","1.5.0-2ubuntu0.1","1.5.0-2ubuntu0.1+esm1","1.5.0-2ubuntu0.1+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"libssh2-1","binary_version":"1.5.0-2ubuntu0.1+esm3"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:Pro:16.04:LTS","cves":[{"id":"CVE-2026-58050","severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H","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_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"score":"medium","type":"Ubuntu"}]},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-58051"},{"severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-66032"},{"id":"CVE-2026-66034","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8799-1.json"}},{"package":{"name":"libssh2","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/libssh2?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.0-1ubuntu0.1+esm1"}]}],"versions":["1.8.0-1","1.8.0-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libssh2-1","binary_version":"1.8.0-1ubuntu0.1+esm1"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"cves_map":{"cves":[{"id":"CVE-2026-58050","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H"},{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","type":"CVSS_V3"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-58051"},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"score":"medium","type":"Ubuntu"}],"id":"CVE-2026-66032"},{"id":"CVE-2026-66034","severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"score":"medium","type":"Ubuntu"}]}],"ecosystem":"Ubuntu:Pro:18.04:LTS"},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8799-1.json"}},{"package":{"name":"libssh2","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/libssh2?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.0-2.1ubuntu0.1+esm1"}]}],"versions":["1.8.0-2.1build1","1.8.0-2.1ubuntu0.1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"libssh2-1","binary_version":"1.8.0-2.1ubuntu0.1+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8799-1.json","cves_map":{"ecosystem":"Ubuntu:Pro:20.04:LTS","cves":[{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H"},{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-58050"},{"id":"CVE-2026-58051","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N"},{"score":"medium","type":"Ubuntu"}]},{"id":"CVE-2026-66032","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}]},{"severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-66034"}]}}},{"package":{"name":"libssh2","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libssh2?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.10.0-3ubuntu0.1"}]}],"versions":["1.9.0-3","1.10.0-2","1.10.0-2build1","1.10.0-3"],"ecosystem_specific":{"binaries":[{"binary_name":"libssh2-1","binary_version":"1.10.0-3ubuntu0.1"}],"availability":"No subscription required"},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:22.04:LTS","cves":[{"id":"CVE-2026-58050","severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H","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_V3"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]},{"id":"CVE-2026-58051","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]},{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-66032"},{"id":"CVE-2026-66034","severity":[{"score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","type":"CVSS_V3"},{"score":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"type":"Ubuntu","score":"medium"}]}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8799-1.json"}}],"schema_version":"1.9.0"}