CVE-2026-34730
Copier `_external_data` allows path traversal and absolute-path local file read without unsafe mode
CVSS Score
5.5
EPSS Score
0.0%
EPSS Percentile
0th
Copier is a library and CLI app for rendering project templates. Prior to version 9.14.1, Copier's _external_data feature allows a template to load YAML files using template-controlled paths. If untrusted templates are in scope, a malicious template can read attacker-chosen YAML-parseable local files that are accessible to the user running Copier and expose their contents in rendered output. This issue has been patched in version 9.14.1.
| CWE | CWE-22 |
| Vendor | copier-org |
| Product | copier |
| Published | Apr 2, 2026 |
| Last Updated | Apr 3, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Attack Vector
Local
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
copier-org / copier
< 9.14.1