CVE-2026-71492
Description
Banks generates meaningful LLM prompts using a simple template language. Prior to version 2.4.5, DirectoryPromptRegistry.set() in src/banks/registries/directory.py interpolates attacker-controlled Prompt.name and Prompt.version values into a Path without canonicalization or containment validation. Relative traversal such as ../victim/foo and an absolute Prompt.name can escape or discard the configured registry root, while overwrite=True permits replacement of existing target files. The poisoned name is persisted in index.json and reconstructed by _load(), allowing the out-of-root path to survive later registry loads. An application that forwards request data into these fields can therefore write Prompt.raw bytes to attacker-chosen paths writable by the application process. This issue is fixed in version 2.4.5.
References
- https://github.com/masci/banks/commit/a215f6d779966945c56e0af5abed1ae5916fd9d3
- https://github.com/masci/banks/pull/77
- https://github.com/masci/banks/releases/tag/v2.4.5
- https://github.com/masci/banks/security/advisories/GHSA-x8wg-4xgc-vr54
- https://github.com/masci/banks/security/advisories/GHSA-x8wg-4xgc-vr54