{"id":"UBUNTU-CVE-2026-56117","details":"dhcpcd through 10.3.2, fixed in commit 78ea09e, contains a heap use-after-free vulnerability in the control socket handling within src/control.c that allows local unprivileged attackers to trigger memory corruption when privilege separation is disabled. Attackers can connect to the control socket and send a privileged command such as -x, causing control_recvdata() to free the client object while the same READ+HANGUP event subsequently reaches control_hangup() with the stale pointer, resulting in a use-after-free condition exploitable in deployments using --disable-privsep or where privsep initialization has failed with the control socket operating in mode 0666.","modified":"2026-06-29T13:56:54.663004307Z","published":"2026-06-23T17:17:00Z","upstream":["CVE-2026-56117"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-56117"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-56117"}],"affected":[{"package":{"name":"dhcpcd","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/dhcpcd?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.0.2-3ubuntu3","1:10.0.5-1","1:10.0.5-2","1:10.0.5-3","1:10.0.5-4","1:10.0.5-5","1:10.0.6-1","1:10.0.6-1ubuntu1","1:10.0.6-1ubuntu2","1:10.0.6-1ubuntu3","1:10.0.6-1ubuntu3.1","1:10.0.6-1ubuntu3.2"],"ecosystem_specific":{"binaries":[{"binary_name":"dhcpcd","binary_version":"1:10.0.6-1ubuntu3.2"},{"binary_version":"1:10.0.6-1ubuntu3.2","binary_name":"dhcpcd-base"},{"binary_name":"dhcpcd5","binary_version":"1:10.0.6-1ubuntu3.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-56117.json"}},{"package":{"name":"dhcpcd","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/dhcpcd?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.1.0-8","1:10.1.0-10","1:10.1.0-11","1:10.1.0-12","1:10.2.4-3","1:10.2.4-4"],"ecosystem_specific":{"binaries":[{"binary_version":"1:10.2.4-4","binary_name":"dhcpcd"},{"binary_version":"1:10.2.4-4","binary_name":"dhcpcd-base"},{"binary_name":"dhcpcd5","binary_version":"1:10.2.4-4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-56117.json"}},{"package":{"name":"dhcpcd","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/dhcpcd?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1:10.2.4-4","1:10.3.0-2","1:10.3.0-3","1:10.3.0-7"],"ecosystem_specific":{"binaries":[{"binary_name":"dhcpcd","binary_version":"1:10.3.0-7"},{"binary_name":"dhcpcd-base","binary_version":"1:10.3.0-7"},{"binary_name":"dhcpcd5","binary_version":"1:10.3.0-7"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-56117.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}