{"id":"UBUNTU-CVE-2026-18938","details":"A flaw was found in p11-kit. A local attacker, or one with equivalent access to a reachable RPC channel, could exploit an integer overflow vulnerability. By sending specially crafted messages, the attacker can cause the system to miscalculate memory allocation for nested attributes. This leads to a memory corruption issue, specifically a heap out-of-bounds write, which can crash the p11-kit RPC parsing process, resulting in a Denial of Service (DoS). This vulnerability is only exploitable on 32 bit systems.","modified":"2026-08-31T17:15:48.350510620Z","published":"2026-08-07T09:16:00Z","related":["USN-8687-1"],"upstream":["CVE-2026-18938"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-18938"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-18938"},{"type":"REPORT","url":"https://access.redhat.com/security/cve/CVE-2026-18938"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8687-1"}],"affected":[{"package":{"name":"p11-kit","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/p11-kit?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.23.9-2ubuntu0.1+esm1"}]}],"versions":["0.23.7-3","0.23.9-2","0.23.9-2ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.23.9-2ubuntu0.1+esm1","binary_name":"libp11-kit0"},{"binary_version":"0.23.9-2ubuntu0.1+esm1","binary_name":"p11-kit"},{"binary_name":"p11-kit-modules","binary_version":"0.23.9-2ubuntu0.1+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/cve/2026/UBUNTU-CVE-2026-18938.json"}},{"package":{"name":"p11-kit","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/p11-kit?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.23.20-1ubuntu0.1+esm1"}]}],"versions":["0.23.17-2","0.23.18.1-2","0.23.19-2","0.23.20-1","0.23.20-1build1","0.23.20-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libp11-kit0","binary_version":"0.23.20-1ubuntu0.1+esm1"},{"binary_name":"p11-kit","binary_version":"0.23.20-1ubuntu0.1+esm1"},{"binary_name":"p11-kit-modules","binary_version":"0.23.20-1ubuntu0.1+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/cve/2026/UBUNTU-CVE-2026-18938.json"}},{"package":{"name":"p11-kit","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/p11-kit?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.24.0-6ubuntu0.1"}]}],"versions":["0.23.22-1build1","0.24.0-5","0.24.0-6","0.24.0-6build1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libp11-kit0","binary_version":"0.24.0-6ubuntu0.1"},{"binary_name":"p11-kit","binary_version":"0.24.0-6ubuntu0.1"},{"binary_name":"p11-kit-modules","binary_version":"0.24.0-6ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-18938.json"}},{"package":{"name":"p11-kit","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/p11-kit?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.25.3-4ubuntu2.2"}]}],"versions":["0.25.0-4ubuntu1","0.25.3-2ubuntu2","0.25.3-4ubuntu1","0.25.3-4ubuntu2","0.25.3-4ubuntu2.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libp11-kit0","binary_version":"0.25.3-4ubuntu2.2"},{"binary_name":"p11-kit","binary_version":"0.25.3-4ubuntu2.2"},{"binary_version":"0.25.3-4ubuntu2.2","binary_name":"p11-kit-modules"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-18938.json"}},{"package":{"name":"p11-kit","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/p11-kit?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.25.5-3ubuntu1","0.25.9-2","0.25.10-1","0.25.10-1ubuntu1","0.26.2-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libp11-kit0","binary_version":"0.26.2-2"},{"binary_name":"p11-kit","binary_version":"0.26.2-2"},{"binary_name":"p11-kit-modules","binary_version":"0.26.2-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-18938.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}