{"id":"DEBIAN-CVE-2026-55653","details":"A flaw was found in OpenSSH. A malicious SSH server can exploit a double free vulnerability in the Diffie-Hellman Group Exchange (DH-GEX) client path. This occurs during FIPS (Federal Information Processing Standards) mode known-group validation when the client processes attacker-controlled DH-GEX group parameters. Successful exploitation leads to client-side process termination, resulting in a Denial of Service (DoS).","modified":"2026-06-25T02:00:39.704777227Z","published":"2026-06-23T04:17:36.600Z","withdrawn":"2026-06-25T02:00:39.704777009Z","upstream":["CVE-2026-55653"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-55653"}],"affected":[{"package":{"name":"openssh","ecosystem":"Debian:11","purl":"pkg:deb/debian/openssh?arch=source&distro=bullseye"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.0p1-1","1:10.0p1-2","1:10.0p1-3","1:10.0p1-4","1:10.0p1-5","1:10.0p1-5~bpo12+2","1:10.0p1-6","1:10.0p1-7","1:10.0p1-7~bpo12+1","1:10.0p1-8","1:10.1p1-1","1:10.1p1-2","1:10.2p1-1","1:10.2p1-2","1:10.2p1-2~bpo13+1","1:10.2p1-3","1:10.2p1-4","1:10.2p1-5","1:10.2p1-6","1:10.2p1-6~bpo13+1","1:10.3p1-1","1:10.3p1-1~bpo13+1","1:10.3p1-2","1:10.3p1-3","1:10.3p1-4","1:8.4p1-5","1:8.4p1-5+deb11u1","1:8.4p1-5+deb11u2","1:8.4p1-5+deb11u3","1:8.4p1-5+deb11u4","1:8.4p1-5+deb11u5","1:8.4p1-5+deb11u6","1:8.4p1-5+deb11u7","1:8.4p1-6","1:8.7p1-1","1:8.7p1-2","1:8.7p1-3","1:8.7p1-4","1:8.8p1-1","1:8.9p1-1","1:8.9p1-2","1:8.9p1-3","1:9.0p1-1","1:9.1p1-1","1:9.1p1-2","1:9.2p1-1","1:9.2p1-2","1:9.3p1-1","1:9.3p1-1+loong64","1:9.3p2-1","1:9.4p1-1","1:9.5p1-1","1:9.5p1-2","1:9.6p1-1","1:9.6p1-2","1:9.6p1-3","1:9.6p1-4","1:9.6p1-5","1:9.7p1-1","1:9.7p1-2","1:9.7p1-3","1:9.7p1-3+hurd.1","1:9.7p1-4","1:9.7p1-5","1:9.7p1-6","1:9.7p1-7","1:9.8p1-1","1:9.8p1-2","1:9.8p1-3","1:9.8p1-4","1:9.8p1-7","1:9.8p1-8","1:9.9p1-1","1:9.9p1-2","1:9.9p1-3","1:9.9p1-3+hurd.1","1:9.9p2-1","1:9.9p2-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55653.json"}},{"package":{"name":"openssh","ecosystem":"Debian:12","purl":"pkg:deb/debian/openssh?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.0p1-1","1:10.0p1-2","1:10.0p1-3","1:10.0p1-4","1:10.0p1-5","1:10.0p1-5~bpo12+2","1:10.0p1-6","1:10.0p1-7","1:10.0p1-7~bpo12+1","1:10.0p1-8","1:10.1p1-1","1:10.1p1-2","1:10.2p1-1","1:10.2p1-2","1:10.2p1-2~bpo13+1","1:10.2p1-3","1:10.2p1-4","1:10.2p1-5","1:10.2p1-6","1:10.2p1-6~bpo13+1","1:10.3p1-1","1:10.3p1-1~bpo13+1","1:10.3p1-2","1:10.3p1-3","1:10.3p1-4","1:9.2p1-2","1:9.2p1-2+deb12u1","1:9.2p1-2+deb12u10","1:9.2p1-2+deb12u2","1:9.2p1-2+deb12u3","1:9.2p1-2+deb12u4","1:9.2p1-2+deb12u5","1:9.2p1-2+deb12u6","1:9.2p1-2+deb12u7","1:9.2p1-2+deb12u8","1:9.2p1-2+deb12u9","1:9.3p1-1","1:9.3p1-1+loong64","1:9.3p2-1","1:9.4p1-1","1:9.5p1-1","1:9.5p1-2","1:9.6p1-1","1:9.6p1-2","1:9.6p1-3","1:9.6p1-4","1:9.6p1-5","1:9.7p1-1","1:9.7p1-2","1:9.7p1-3","1:9.7p1-3+hurd.1","1:9.7p1-4","1:9.7p1-5","1:9.7p1-6","1:9.7p1-7","1:9.8p1-1","1:9.8p1-2","1:9.8p1-3","1:9.8p1-4","1:9.8p1-7","1:9.8p1-8","1:9.9p1-1","1:9.9p1-2","1:9.9p1-3","1:9.9p1-3+hurd.1","1:9.9p2-1","1:9.9p2-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55653.json"}},{"package":{"name":"openssh","ecosystem":"Debian:13","purl":"pkg:deb/debian/openssh?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.0p1-7","1:10.0p1-7+deb13u1","1:10.0p1-7+deb13u2","1:10.0p1-7+deb13u3","1:10.0p1-7+deb13u4","1:10.0p1-8","1:10.1p1-1","1:10.1p1-2","1:10.2p1-1","1:10.2p1-2","1:10.2p1-2~bpo13+1","1:10.2p1-3","1:10.2p1-4","1:10.2p1-5","1:10.2p1-6","1:10.2p1-6~bpo13+1","1:10.3p1-1","1:10.3p1-1~bpo13+1","1:10.3p1-2","1:10.3p1-3","1:10.3p1-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55653.json"}},{"package":{"name":"openssh","ecosystem":"Debian:14","purl":"pkg:deb/debian/openssh?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.0p1-7","1:10.0p1-8","1:10.1p1-1","1:10.1p1-2","1:10.2p1-1","1:10.2p1-2","1:10.2p1-2~bpo13+1","1:10.2p1-3","1:10.2p1-4","1:10.2p1-5","1:10.2p1-6","1:10.2p1-6~bpo13+1","1:10.3p1-1","1:10.3p1-1~bpo13+1","1:10.3p1-2","1:10.3p1-3","1:10.3p1-4"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55653.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L"}]}