CVE-2025-55201
HIGHCVSS 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Lifecycle Timeline
3Tags
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.
Analysis
Copier library and CLI app for rendering project templates. Rated high severity (CVSS 8.5), this vulnerability is no authentication required, low attack complexity. No vendor patch available.
Technical Context
This vulnerability is classified as Path Traversal (CWE-22), which allows attackers to access files and directories outside the intended path. 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. Version information: Prior to 9.9.1.
Affected Products
See vendor advisory for affected versions.
Remediation
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate and canonicalize file paths. Use chroot or sandboxing. Reject input containing path separators or '../' sequences.
Priority Score
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External POC / Exploit Code
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