Mix deps.partition · Insecure Temporary File Vulnerability
Affects elixirSource GCVE Database
Not known to be exploited · CVSS 5.4 Medium.
Data as of 5 Nov 2026, 12:34 UTC
Thin evidence
One scorer or none| CNA (EEF) | CVSS 4.0 | 5.4 |
|---|
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 18.04 LTSelixirpkg:deb/ubuntu/elixir?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Ubuntu 16.04 LTSelixirpkg:deb/ubuntu/elixir?arch=source&distro=xenialOther threats | Affected
| Fixed in– |
Ubuntu 14.04 LTSelixirpkg:deb/ubuntu/elixir?arch=source&distro=trustyOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2026-97209 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-97209 (opens in a new tab)
- cna.erlef.org/cves/CVE-2026-97209.html (opens in a new tab)
- github.com/elixir-lang/elixir/commit/55eb91220a1de14dc5aa27029d1f45b0f5832b2d (opens in a new tab)
- github.com/elixir-lang/elixir/commit/7f3d95b60c28ae3026a5c1bf943166391245bfd1 (opens in a new tab)
- github.com/elixir-lang/elixir/commit/9adbe955c8664f4be77d879dd38c003dd39fa777 (opens in a new tab)
- github.com/elixir-lang/elixir/security/advisories/GHSA-96q6-xhwp-fc8q (opens in a new tab)
- osv.dev/vulnerability/EEF-CVE-2026-97209 (opens in a new tab)