Vulnerability · Published Aug 18, 2025 · Assigned by GitHub_M

CVE-2025-55201Copier safe template has arbitrary filesystem read/write access

High 8.5

In plain English

A high-severity path traversal in copier from copier-org. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)8.5High
Exploit odds (30 days)0.3%top 82.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Copier library and CLI app for rendering project templates. Prior to 9.9.1, a safe template can currently read and write arbitrary files because Copier exposes a few pathlib.Path objects in the Jinja context which have unconstrained I/O methods. This effectively renders the security model w.r.t. filesystem access useless. This vulnerability is fixed in 9.9.1.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
PyPIcopier9.9.1GHSA-3xw7-v6cj-5q8h
PyPIcopier9.9.1PYSEC-2026-1271

Affected products (as reported)

VendorProductVersions
copier-org copier < 9.9.1

Weakness: CWE-22 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References