---
id: CVE-2026-62999
title: Copier is a library and CLI app for rendering project templates
summary: >-
  Copier is a library and CLI app for rendering project templates. From 9.5.0
  through 9.16.0, percent-encoded parent-directory segments or encoded path
  separators in a template URL can match a configured trusted repository prefix
  before an…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-22
  - CWE-180
vendor: copier-org
product: copier
affected:
  - 'copier >= 9.5.0, <= 9.16.0'
published: '2026-07-31'
updated: '2026-09-09'
sourceUpdated: '2026-09-09T20:55:04.493'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-62999'
references:
  - url: >-
      https://github.com/copier-org/copier/commit/7408f0d6287a7bf452715fd9f25dc54eaba3c295
    label: security-advisories@github.com
  - url: 'https://github.com/copier-org/copier/releases/tag/v9.17.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/copier-org/copier/security/advisories/GHSA-34mv-rjq9-5mch
    label: security-advisories@github.com
  - url: >-
      https://github.com/copier-org/copier/security/advisories/GHSA-34mv-rjq9-5mch
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-07-31T19:59:06.929791Z'
ingestedAt: '2026-09-14T12:22:18.666Z'
epss: 0.00441
epssPercentile: 0.35724
---

## Overview

Copier is a library and CLI app for rendering project templates. From 9.5.0 through 9.16.0, percent-encoded parent-directory segments or encoded path separators in a template URL can match a configured trusted repository prefix before an HTTP server or Git transport decodes the path, allowing unsafe template features from a repository outside the trusted prefix to run after user interaction. This issue is fixed in version 9.17.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.