{"id":"CVE-2026-34177","state":"PUBLISHED","title":"VM lowlevel restriction bypass via raw.apparmor and raw.qemu.conf","description":"Canonical LXD versions 4.12 through 6.7 contain an incomplete denylist in isVMLowLevelOptionForbidden (lxd/project/limits/permissions.go), which omits raw.apparmor and raw.qemu.conf from the set of keys blocked under the restricted.virtual-machines.lowlevel=block project restriction. A remote attacker with can_edit permission on a VM instance in a restricted project can inject an AppArmor rule and a QEMU chardev configuration that bridges the LXD Unix socket into the guest VM, enabling privilege escalation to LXD cluster administrator and subsequently to host root.","publishedAt":"2026-04-09T09:15:27.532Z","updatedAt":"2026-04-09T12:12:48.251Z","severity":{"score":9.1,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H","source":"canonical"},"assigner":"canonical","products":["Canonical lxd"],"affected":[{"vendor":"Canonical","product":"lxd","packageName":"lxd","defaultStatus":"unaffected","versions":[{"version":"4.12.0","status":"affected","lessThan":"5.0.7","versionType":"semver"},{"version":"5.1.0","status":"affected","lessThan":"5.21.5","versionType":"semver"},{"version":"6.0.0","status":"affected","lessThan":"6.8.0","versionType":"semver"}],"platforms":["Linux"],"collectionURL":"https://github.com/canonical","repo":"https://github.com/canonical/lxd","programFiles":["permissions.go"]}],"references":["https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f","https://github.com/canonical/lxd/pull/17909"],"weaknesses":["CWE-184"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/34xxx/CVE-2026-34177.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-34177","state":"PUBLISHED","datePublished":"2026-04-09T09:15:27.532Z","dateUpdated":"2026-04-09T12:12:48.251Z","assignerShortName":"canonical","assignerOrgId":"cc1ad9ee-3454-478d-9317-d3e869d708bc","dateReserved":"2026-03-26T09:24:08.448Z"},"containers":{"cna":{"title":"VM lowlevel restriction bypass via raw.apparmor and raw.qemu.conf","descriptions":[{"lang":"en","value":"Canonical LXD versions 4.12 through 6.7 contain an incomplete denylist in isVMLowLevelOptionForbidden (lxd/project/limits/permissions.go), which omits raw.apparmor and raw.qemu.conf from the set of keys blocked under the restricted.virtual-machines.lowlevel=block project restriction. A remote attacker with can_edit permission on a VM instance in a restricted project can inject an AppArmor rule and a QEMU chardev configuration that bridges the LXD Unix socket into the guest VM, enabling privilege escalation to LXD cluster administrator and subsequently to host root."}],"affected":[{"vendor":"Canonical","product":"lxd","packageName":"lxd","defaultStatus":"unaffected","versions":[{"version":"4.12.0","status":"affected","lessThan":"5.0.7","versionType":"semver"},{"version":"5.1.0","status":"affected","lessThan":"5.21.5","versionType":"semver"},{"version":"6.0.0","status":"affected","lessThan":"6.8.0","versionType":"semver"}],"platforms":["Linux"],"collectionURL":"https://github.com/canonical","repo":"https://github.com/canonical/lxd","programFiles":["permissions.go"]}],"references":[{"url":"https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f","name":"VM lowlevel restriction bypass via raw.apparmor and raw.qemu.conf","tags":["vdb-entry","vendor-advisory"]},{"url":"https://github.com/canonical/lxd/pull/17909","name":"lxd: Prevent use of raw.apparmor and raw.qemu.conf when low level options are blocked","tags":["patch","issue-tracking"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseSeverity":"CRITICAL","baseScore":9.1,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-184","lang":"en","description":"CWE-184 Incomplete list of disallowed inputs","type":"CWE"}]}],"providerMetadata":{"shortName":"canonical","orgId":"cc1ad9ee-3454-478d-9317-d3e869d708bc","dateUpdated":"2026-04-09T09:15:27.532Z"},"credits":[{"lang":"en","value":"Miha Purg","type":"finder"}],"source":{"discovery":"INTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/canonical/lxd/security/advisories/GHSA-fm2x-c5qw-4h6f","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-09T12:12:43.482752Z","id":"CVE-2026-34177","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-04-09T12:12:48.251Z"}}]}}}