CVE-2026-96612

Path traversal in Hex via unvalidated dependency app names

Published Oct 12, 2026 CVSS 4.0 · 7.5 High EPSS < 1% KEV · Not listed
Description
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in hexpm hex allows a malicious package publisher to delete a directory outside the project's deps directory and extract package files into it when a developer fetches dependencies.

A package release's requirements carry an app label that names the dependency's OTP application. Hex takes this label from the repository's signed registry and uses it as the dependency's application name without validating it (Hex.RemoteConverger.deps/2, Hex.Mix.to_lock/1). Mix derives the dependency's checkout directory as deps/<app>, and Hex.SCM.update/1 runs File.rm_rf!/1 on that directory and unpacks the package into it. hex.pm only checks the label's length, so a publisher can set it to a value such as ../../target. When a project depends on such a release directly or transitively, mix deps.get or mix deps.update deletes the directory the label resolves to and writes the labelled package's files there. This happens before any dependency code is compiled.

This issue affects hex: from 0.6.0 before 2.5.2.

Remediation

Vendor Solution

Upgrade Hex to 2.5.2 or later, for example with mix local.hex. Hex then skips package releases that give a dependency an application name other than a letter followed by letters, digits, _ and -, and warns about them. Resolution fails if no other release of the package fits the requirements.


Vendor Workaround

Before running mix deps.get on a mix.lock from an untrusted change, check that every key in mix.lock is a plain application name without /, \ or ... There's no workaround for new dependency resolution with mix deps.update or mix deps.get without a lock entry.

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'}

threat_severity

Important

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in hexpm hex allows a malicious package publisher to delete a directory outside the project's deps directory and extract package files into it when a developer fetches dependencies. A package release's requirements carry an app label that names the dependency's OTP application. Hex takes this label from the repository's signed registry and uses it as the dependency's application name without validating it (Hex.RemoteConverger.deps/2, Hex.Mix.to_lock/1). Mix derives the dependency's checkout directory as deps/<app>, and Hex.SCM.update/1 runs File.rm_rf!/1 on that directory and unpacks the package into it. hex.pm only checks the label's length, so a publisher can set it to a value such as ../../target. When a project depends on such a release directly or transitively, mix deps.get or mix deps.update deletes the directory the label resolves to and writes the labelled package's files there. This happens before any dependency code is compiled. This issue affects hex: from 0.6.0 before 2.5.2.
Title Path traversal in Hex via unvalidated dependency app names
First Time appeared Hexpm
Hexpm hex
Weaknesses CWE-22
CPEs cpe:2.3:a:hexpm:hex:*:*:*:*:*:*:*:*
Vendors & Products Hexpm
Hexpm hex
References
Metrics cvssV4_0

{'score': 7.5, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
EEF
Published
Updated
Nov 11, 2026, 1:28 PM
Reserved
Oct 1, 2026, 9:00 AM
Status
Deferred
Published
Oct 12, 2026, 4:17 PM
Modified
Nov 11, 2026, 2:17 PM
Severity
Important
Public date
Oct 12, 2026, 3:39 PM