Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in erlang rebar3 allows a malicious package publisher to delete a directory outside the project's _build directory and extract package files into it when a developer fetches dependencies. A package release's dependencies in a Hex registry carry an app field that names the dependency's OTP application. rebar3 uses this field as the dependency's name without validating it (rebar_packages:parse_deps/1) and builds the dependency's directory from that name (rebar_app_utils:dep_to_app/7). rebar_fetch:download_source_online/2 deletes that directory with rm -rf and moves the fetched package into it. hex.pm didn't restrict the field to a directory name before 2026-10-12, so a publisher could set it to a value such as ../../../../target. When a project depends on such a release directly or transitively, rebar3 get-deps deletes the directory the name resolves to and writes the dependency's files there. This happens before the dependency's own rebar.config.script is evaluated, and get-deps compiles nothing. This issue affects rebar3: from 3.7.0-rc1 before 3.27.2.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Network (N)
|
Exploit possible à distance via réseau (HTTP, API, etc.) |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
None (N)
|
Aucune authentification requise |
|
UI (Interaction Utilisateur)
User Interaction
|
Required (R)
|
NĂ©cessite une action utilisateur (clic lien, ouverture fichier, etc.) |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
High (H)
|
Divulgation totale d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
High (H)
|
Modification totale des données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |
Path traversal in rebar3 via unvalidated dependency app names