{"id":"CVE-2026-90616","details":"In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.","aliases":["GHSA-8688-9x26-hhxj"],"modified":"2026-09-15T03:30:48.155885539Z","published":"2026-09-12T20:00:58.476Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90616.json","cna_assigner":"mitre","cwe_ids":["CWE-61"]},"references":[{"type":"WEB","url":"https://www.openwall.com/lists/oss-security/2026/08/11/9"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90616.json"},{"type":"ADVISORY","url":"https://github.com/flatpak/flatpak/security/advisories/GHSA-8688-9x26-hhxj"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90616"},{"type":"PACKAGE","url":"https://github.com/flatpak/flatpak"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/flatpak/flatpak","events":[{"introduced":"0"},{"fixed":"abc06c8bf434171e931426e76a9eb0bfe17cfabd"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"1.18.1"}],"source":["AFFECTED_FIELD","DESCRIPTION"]}}],"versions":["1.18.0","1.17.7","1.17.6","1.17.5","1.17.4","1.17.3","1.17.2","1.17.1","1.17.0","1.16.1","1.16.0","1.15.91","1.15.12","1.15.11","1.15.10","1.15.9","1.15.8","1.15.7","1.15.6","1.15.4","1.15.3","1.15.2","1.15.1","1.15.0","1.14.0","1.13.3","1.13.2","1.13.1","1.11.2","1.12.0","1.11.3","1.11.1","1.10.1","1.10.0","1.9.3","1.9.2","1.9.1","1.8.0","1.7.3","1.7.2","1.7.1","1.6.2","1.6.1","1.6.0","1.5.2","1.5.1","1.5.0","1.4.0","1.3.4","1.3.3","1.3.2","1.3.1","1.3.0","1.2.1","1.2.0","1.1.3","1.1.2","1.1.1","1.1.0","1.0.3","1.0.2","1.0.1","1.0.0","0.99.3","0.99.2","0.99.1","0.11.8.3","0.11.8.2","0.11.8.1","0.11.8","0.11.7","0.11.6","0.11.5","0.11.4","0.11.3","0.11.2","0.11.1","0.10.2","0.10.1","0.10.0","0.9.99","0.9.98.2","0.9.98.1","0.9.98","0.9.12","0.9.11","0.9.10","0.9.9","0.9.8","0.9.7","0.9.6","0.9.5","0.9.4","0.9.3","0.9.2","0.9.1","0.8.1","0.8.0","0.6.14","0.6.13","0.6.12","0.6.11","0.6.10","0.6.9","0.6.8","0.6.7","0.6.6","0.6.5","0.6.4","0.6.3","0.6.2","0.6.1","0.6.0","0.5.2","0.5.1","0.5.0","0.4.13","0.4.12","0.4.11","0.4.10","0.4.9","0.4.8","0.4.7","0.4.6","0.4.5","0.4.4","0.4.3","0.4.2.1","0.4.2","0.4.1","0.4.0","0.3.6","0.3.5","0.3.4","0.3.3","0.3.2","0.3.1","0.3","0.2.1","0.2","0.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90616.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}