High severity · published Aug 18, 2025
CVE-2025-55201
Copier safe template has arbitrary filesystem read/write access
8.5
CVSS
0.3%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
copier · copier-org
< 9.9.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-55201
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-55201
github.com
https://github.com/copier-org/copier/commit/3feea3b3ff3c20d80cbb16a2f3b9567ffc5606d1
github.com
https://github.com/copier-org/copier/security/advisories/GHSA-3xw7-v6cj-5q8h
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