{"schemaVersion":3,"id":"CVE-2026-40243","aliases":["UBUNTU-CVE-2026-40243","DEBIAN-CVE-2026-40243","GHSA-c839-4qxr-j4x3","GO-2026-5319"],"status":"published","duplicateOf":null,"title":null,"description":"Incus is a system container and virtual machine manager. In versions before 7.0.0, broken TLS validation logic in the OVN database connection logic can allow connections to an attacker's OVN database. The OVN client implementations disable Go standard TLS server verification and replace it with custom peer-certificate verification logic. That replacement verifier does not anchor trust in the configured CA certificate. Instead, it constructs the verification root set from certificates supplied by the peer during the handshake, so the configured CA is parsed but not used as the trust anchor for the final verification decision.\n\nIn OVN-enabled deployments that use these SSL database connection paths, an attacker able to impersonate or intercept the OVN endpoint on the management network can present a rogue self-signed certificate chain, and Incus will accept this certificate as valid. This issue defeats the intended CA-based trust model for OVN database connections and permits endpoint impersonation by an active attacker in a suitable network position. This issue is fixed in version 7.0.0.","dates":{"published":"2026-05-06T20:38:22.590Z","modified":"2026-05-07T14:03:42.997Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.8,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"CVE.org","score":2.3,"severity":"low","vector":"CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"OSV · Ubuntu","score":2.3,"severity":"low","vector":"CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","exploitability":null,"impact":null,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":4.8,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","exploitability":5.6,"impact":4.2,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":4.8,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","exploitability":5.6,"impact":4.2,"computed":true},{"version":"4.0","versionLabel":"v4.0","source":"OSV · Go","score":2.3,"severity":"low","vector":"CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","exploitability":null,"impact":null,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Go","score":2.3,"severity":"low","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N","exploitability":2.1,"impact":2.3,"computed":true},{"version":"4.0","versionLabel":"v4.0","source":"NVD","score":2.3,"severity":"low","vector":"CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":4.8,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00222,"percentile":0.11923,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0.04900000000000002,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.00173},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00222,"percentile":0.11923}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00173,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00222,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00222,"percentile":0.11923}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[{"id":"GITHUB_LXC_INCUS","name":"Incus","source":"github","url":"https://github.com/lxc/incus/security/advisories/GHSA-56mx-8g9f-5crf","maturity":"poc","reliabilityScore":0.3,"verified":false,"type":null,"platforms":[],"requiresAuth":null,"exploitdb":null,"metasploit":null}],"exploitCount":1,"weaknesses":[{"id":"CWE-295","name":"Improper Certificate Validation","description":"The product does not validate, or incorrectly validates, a certificate.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/295.html"}],"affected":[{"vendor":"debian","product":"incus","name":"incus","label":"incus","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/incus","purlType":"deb","versions":[{"text":"< 6.0.4-2+deb13u7","noFixRecorded":false,"fixedIn":null},{"text":"< 7.0.0-1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 6.0.4-2+deb13u7 | < 7.0.0-1","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"incus","name":"incus","label":"incus","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/incus","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"github.com/lxc","product":"incus","name":"github.com/lxc/incus","label":"incus","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/lxc/incus","purlType":"golang","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"github.com/lxc/incus","product":"v6","name":"github.com/lxc/incus/v6","label":"v6","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/lxc/incus/v6","purlType":"golang","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"github.com/lxc/incus","product":"v7","name":"github.com/lxc/incus/v7","label":"v7","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/lxc/incus/v7","purlType":"golang","versions":[{"text":"< 7.0.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 7.0.0","eol":null,"hubHref":null},{"vendor":"github.com/lxc/incus/v6/cmd","product":"incusd","name":"github.com/lxc/incus/v6/cmd/incusd","label":"incusd","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/lxc/incus/v6/cmd/incusd","purlType":"golang","versions":[{"text":"< 7.0.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 7.0.0","eol":null,"hubHref":null},{"vendor":"linuxcontainers","product":"incus","name":"incus","label":"incus","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 7.0.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 7.0.0","eol":null,"hubHref":"/vendor/linuxcontainers/incus"},{"vendor":"lxc","product":"incus","name":"incus","label":"incus","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 7.0.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 7.0.0","eol":null,"hubHref":"/vendor/lxc/incus"}],"affectedCount":8,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/lxc/incus/security/advisories/GHSA-c839-4qxr-j4x3","label":"github.com/lxc/incus/security/advisories/GHSA-c839-4qxr-j4x3","hostname":"github.com","tags":["X Refsource CONFIRM","REPORT","WEB","Advisory","Exploit","Vendor Advisory"]},{"url":"https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icnb.go","label":"github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icnb.go","hostname":"github.com","tags":["X Refsource MISC","WEB","Product"]},{"url":"https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icsb.go","label":"github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_icsb.go","hostname":"github.com","tags":["X Refsource MISC","WEB","Product"]},{"url":"https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_nb.go","label":"github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_nb.go","hostname":"github.com","tags":["X Refsource MISC","WEB","Product"]},{"url":"https://github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_sb.go","label":"github.com/lxc/incus/blob/v6.22.0/internal/server/network/ovn/ovn_sb.go","hostname":"github.com","tags":["X Refsource MISC","WEB","Product"]},{"url":"https://ubuntu.com/security/CVE-2026-40243","label":"ubuntu.com/security/CVE-2026-40243","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-40243","label":"www.cve.org/CVERecord?id=CVE-2026-40243","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://github.com/lxc/incus/pull/3273","label":"github.com/lxc/incus/pull/3273","hostname":"github.com","tags":["REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-40243","label":"security-tracker.debian.org/tracker/CVE-2026-40243","hostname":"security-tracker.debian.org","tags":["Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40243","label":"nvd.nist.gov/vuln/detail/CVE-2026-40243","hostname":"nvd.nist.gov","tags":["Advisory"]},{"url":"https://github.com/lxc/incus","label":"github.com/lxc/incus","hostname":"github.com","tags":["PACKAGE"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:21483-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:21483-1"]},"timeline":[{"kind":"published","date":"2026-05-06T20:38:22.590Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-05-07T14:03:42.997Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":29,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T01:03:05.159Z","stale":false,"partial":false}}