{"id":"USN-8090-2","summary":"openssh vulnerabilities","details":"USN-8090-1 fixed vulnerabilities in OpenSSH. This update provides the\ncorresponding updates for Ubuntu 20.04 LTS.\n\nOriginal advisory details:\n\nJeremy Brown discovered that the OpenSSH GSSAPI Key Exchange incorrectly\nhandled disconnecting clients. In non-default configurations where the\nGSSAPIKeyExchange setting is enabled, a remote attacker could use this\nissue to cause OpenSSH to crash, resulting in a denial of service, or\npossibly execute arbitrary code. (CVE-2026-3497)\n\nDavid Leadbeater discovered that OpenSSH incorrectly handled certain\ncontrol characters in usernames. When untrusted usernames and the\nProxyCommand are being used, an attacker could possibly use this issue to\nexecute arbitrary code. (CVE-2025-61984)\n\nDavid Leadbeater discovered that OpenSSH incorrectly handled NULL\ncharacters in ssh:// URIs. When the ProxyCommand is being used, an attacker\ncould possibly use this issue to execute arbitrary code. (CVE-2025-61985)","modified":"2026-03-17T06:42:45.335557Z","published":"2026-03-12T18:31:57Z","related":["UBUNTU-CVE-2025-61984","UBUNTU-CVE-2025-61985","UBUNTU-CVE-2026-3497"],"upstream":["CVE-2025-61984","CVE-2025-61985","CVE-2026-3497","UBUNTU-CVE-2025-61984","UBUNTU-CVE-2025-61985","UBUNTU-CVE-2026-3497"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8090-2"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-61984"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-61985"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-3497"}],"affected":[{"package":{"name":"openssh","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/openssh@1:8.2p1-4ubuntu0.13+esm1?arch=source&distro=esm-infra/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:8.2p1-4ubuntu0.13+esm1"}]}],"versions":["1:8.0p1-6build1","1:8.1p1-1","1:8.1p1-5","1:8.2p1-4","1:8.2p1-4ubuntu0.1","1:8.2p1-4ubuntu0.2","1:8.2p1-4ubuntu0.3","1:8.2p1-4ubuntu0.4","1:8.2p1-4ubuntu0.5","1:8.2p1-4ubuntu0.7","1:8.2p1-4ubuntu0.8","1:8.2p1-4ubuntu0.9","1:8.2p1-4ubuntu0.10","1:8.2p1-4ubuntu0.11","1:8.2p1-4ubuntu0.12","1:8.2p1-4ubuntu0.13"],"ecosystem_specific":{"binaries":[{"binary_name":"openssh-client","binary_version":"1:8.2p1-4ubuntu0.13+esm1"},{"binary_name":"openssh-server","binary_version":"1:8.2p1-4ubuntu0.13+esm1"},{"binary_name":"openssh-sftp-server","binary_version":"1:8.2p1-4ubuntu0.13+esm1"},{"binary_name":"openssh-tests","binary_version":"1:8.2p1-4ubuntu0.13+esm1"},{"binary_name":"ssh","binary_version":"1:8.2p1-4ubuntu0.13+esm1"},{"binary_name":"ssh-askpass-gnome","binary_version":"1:8.2p1-4ubuntu0.13+esm1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8090-2.json","cves_map":{"cves":[{"severity":[{"score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N","type":"CVSS_V3"},{"score":"low","type":"Ubuntu"}],"id":"CVE-2025-61984"},{"severity":[{"score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N","type":"CVSS_V3"},{"score":"low","type":"Ubuntu"}],"id":"CVE-2025-61985"},{"severity":[{"score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N","type":"CVSS_V4"},{"score":"medium","type":"Ubuntu"}],"id":"CVE-2026-3497"}],"ecosystem":"Ubuntu:Pro:20.04:LTS"}}}],"schema_version":"1.7.5"}