CVE-2026-34726

Published: Apr 02, 2026 Last Modified: Apr 02, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 4,4
Source: [email protected]
Attack Vector: local
Attack Complexity: low
Privileges Required: none
User Interaction: required
Scope: unchanged
Confidentiality: low
Integrity: low
Availability: none

Description

AI Translation Available

Copier is a library and CLI app for rendering project templates. Prior to version 9.14.1, Copier's _subdirectory setting is documented as the subdirectory to use as the template root. However, the current implementation accepts parent-directory traversal such as .. and uses it directly when selecting the template root. As a result, a template can escape its own directory and make Copier render files from the parent directory without --UNSAFE. This issue has been patched in version 9.14.1.

22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Integrity Confidentiality Availability
Potential Impacts:
Execute Unauthorized Code Or Commands Modify Files Or Directories Read Files Or Directories Dos: Crash, Exit, Or Restart
Applicable Platforms
Technologies: AI/ML
Likelihood of Exploit: High
View CWE Details
https://github.com/copier-org/copier/commit/cb80a3ffc9c3787…
https://github.com/copier-org/copier/commit/cb80a3ffc9c3787de3ed837e04ca29a0ff8…
https://github.com/copier-org/copier/releases/tag/v9.14.1
https://github.com/copier-org/copier/releases/tag/v9.14.1
https://github.com/copier-org/copier/security/advisories/GH…
https://github.com/copier-org/copier/security/advisories/GHSA-85v3-4m8g-hrh6