{"id":"CVE-2026-96276","title":"If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working …","summary":"If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working …","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","cwe":["CWE-22"],"vendor":"Red Hat","product":"flatpak","affected":["flatpak (all versions)","flatpak (all versions)","flatpak (all versions)","flatpak (all versions)"],"published":"2026-09-23","updated":"2026-09-27","sourceUpdated":"2026-09-27T21:17:03.160","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-96276","references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-96276","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2539418","label":"secalert@redhat.com"},{"url":"https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm","label":"secalert@redhat.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96276.json"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-96276"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-96276"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00436,"epssPercentile":0.37711,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-09-23T15:28:10.393280Z"},"ingestedAt":"2026-09-23T15:26:23.424Z","slug":"CVE-2026-96276","body":"## Overview\n\nIf a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working directory, since the target path is resolved via a function that allows `..` traversal.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-09-27 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96276.json)","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":211679,"id":"CVE-2026-96276","ts":1790542715003,"field":"cvss","old":"9.8","new":"6.5"},{"seq":211678,"id":"CVE-2026-96276","ts":1790542715003,"field":"severity","old":"critical","new":"medium"},{"seq":209779,"id":"CVE-2026-96276","ts":1790180881576,"field":"cvss","old":null,"new":"9.8"},{"seq":209778,"id":"CVE-2026-96276","ts":1790180881576,"field":"severity","old":"none","new":"critical"}]}