CVE-2026-97209
Medium 5.4
Description
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.
Metrics
- CVSS 4.0
-
5.4 (MEDIUM)
Score source: CNA
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/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 - EPSS — exploit probability
- 0% (percentile: 2) as of 1 November 2026
- CWE
- CWE-377
References
- https://cna.erlef.org/cves/CVE-2026-97209.html
- https://github.com/elixir-lang/elixir/commit/55eb91220a1de14dc5aa27029d1f45b0f5…
- https://github.com/elixir-lang/elixir/commit/7f3d95b60c28ae3026a5c1bf9431663912…
- https://github.com/elixir-lang/elixir/commit/9adbe955c8664f4be77d879dd38c003dd3…
- https://github.com/elixir-lang/elixir/security/advisories/GHSA-96q6-xhwp-fc8q
- https://osv.dev/vulnerability/EEF-CVE-2026-97209
- https://github.com/elixir-lang/elixir/security/advisories/GHSA-96q6-xhwp-fc8q