CVE-2026-34730

Name: CVE-2026-34730
Creator: NVD / NIST
Published: 2026-04-02T19:21:32.56+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.29%

Last modified Jun 17, 2026

CVE-2026-34730 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. 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. EPSS estimates a 0.29% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.29%

20.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

Affected Software

Vendor	Product	Versions
Copier-Org	Copier	< 9.14.1

References

https://github.com/copier-org/copier/commit/5413062eb17b73dc885f5e645cdc161e69ef641bPatch
https://github.com/copier-org/copier/releases/tag/v9.14.1Release Notes
https://github.com/copier-org/copier/security/advisories/GHSA-hgjq-p8cr-gg4hExploit, Vendor Advisory
https://github.com/copier-org/copier/security/advisories/GHSA-hgjq-p8cr-gg4hExploit, Vendor Advisory

Timeline

Published: Apr 2, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-34730?

How severe is CVE-2026-34730?

CVE-2026-34730 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.

How do I fix CVE-2026-34730?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-34730?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST