{"id":"UBUNTU-CVE-2026-97209","details":"Insecure Temporary File vulnerability in Mix deps.partition in Elixir allows a local user to execute code as another user via a swapped partition config file. Partitioned dependency compilation passes the project configuration to each partition VM through a file in a fixed-name directory under the shared system temporary directory, and the partition trusts what it reads back. Another local user on the same host can exploit this during a mix deps.compile run that uses partitioned compilation. Mix.Tasks.Deps.Partition.server/4 in lib/mix/lib/mix/tasks/deps.partition.ex creates the directory with File.mkdir_p/1, which accepts an existing directory without checking its owner, so a user who created it first can replace the file before client/0 reads it. This issue affects mix: from 1.20.0-rc.4 before 1.20.5.","modified":"2026-10-31T03:30:15.032520803Z","published":"2026-10-30T00:00:00Z","upstream":["CVE-2026-97209"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-97209"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-97209"},{"type":"REPORT","url":"https://cna.erlef.org/cves/CVE-2026-97209.html"},{"type":"REPORT","url":"https://github.com/elixir-lang/elixir/commit/55eb91220a1de14dc5aa27029d1f45b0f5832b2d"},{"type":"REPORT","url":"https://github.com/elixir-lang/elixir/commit/7f3d95b60c28ae3026a5c1bf943166391245bfd1"},{"type":"REPORT","url":"https://github.com/elixir-lang/elixir/commit/9adbe955c8664f4be77d879dd38c003dd39fa777"},{"type":"REPORT","url":"https://github.com/elixir-lang/elixir/security/advisories/GHSA-96q6-xhwp-fc8q"},{"type":"REPORT","url":"https://osv.dev/vulnerability/EEF-CVE-2026-97209"}],"affected":[{"package":{"name":"elixir","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/elixir?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.1-1","0.7.1-2","0.7.1-4build0.14.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.7.1-4build0.14.04.1","binary_name":"python-elixir"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-97209.json"}},{"package":{"name":"elixir","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/elixir?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.1-3","0.7.1-4build0.16.04.1"],"ecosystem_specific":{"binaries":[{"binary_name":"python-elixir","binary_version":"0.7.1-4build0.16.04.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-97209.json"}},{"package":{"name":"elixir","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/elixir?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.1-4build1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.7.1-4build1","binary_name":"python-elixir"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-97209.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}