CVE-2026-34726

Published: Apr 2, 2026Modified: Jul 24, 2026

4.4

Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N

Exploitability: 1.8 / Impact: 2.5

Source: security-advisories@github.com (Secondary)

Description

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.

Affected (1)

Products: Copier Org: Copier

1 product

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Copier Org Copier	Before 9.14.1

Related CWEs

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

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

References (4)

https://github.com/copier-org/copier/commit/cb80a3ffc9c3787de3ed837e04ca29a0ff8ca3df

Source: security-advisories@github.com

Patch

https://github.com/copier-org/copier/releases/tag/v9.14.1

Source: security-advisories@github.com

Release Notes

https://github.com/copier-org/copier/security/advisories/GHSA-85v3-4m8g-hrh6

Source: security-advisories@github.com

ExploitVendor Advisory

https://github.com/copier-org/copier/security/advisories/GHSA-85v3-4m8g-hrh6

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

ExploitVendor Advisory

Timeline

No history available yet.