CVE-2026-23968 (GCVE-0-2026-23968)

Vulnerability from cvelistv5 – Published: 2026-01-21 22:13 – Updated: 2026-01-22 16:49
VLAI
Title
Copier safe template has arbitrary filesystem read access via symlinks when _preserve_symlinks: false
Summary
Copier is a library and CLI app for rendering project templates. Prior to version 9.11.2, Copier suggests that it's safe to generate a project from a safe template, i.e. one that doesn't use unsafe features like custom Jinja extensions which would require passing the `--UNSAFE,--trust` flag. As it turns out, a safe template can currently include arbitrary files/directories outside the local template clone location by using symlinks along with `_preserve_symlinks: false` (which is Copier's default setting). Version 9.11.2 patches the issue.
Severity
6.8 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-22 15:09 UTC
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7761 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
copier-org copier Affected: < 9.11.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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