Affected: MervinPraison PraisonAI

PraisonAI (pip package praisonaiagents) before 1.6.78 automatically loads defaults from a project-local .praisonai/config.toml when constructing an Agent, and does not validate the defaults.output.output_file path. A repository-controlled config file can set output_file to an absolute or '..' traversal path; when the developer subsequently calls agent.start() without explicitly passing an output parameter, PraisonAI writes the agent response to that path (creating parent directories as needed), allowing an untrusted checked-out project to overwrite files outside the project root with the privileges of the user running PraisonAI.

Affected: PyPI: praisonaiagents

# Project config can auto-save agent output outside the project root

## Summary

`praisonaiagents` automatically reads project-local `.praisonai/config.toml` defaults when constructing an `Agent`. A repository-controlled config can set `defaults.output.output_file` to an absolute path or a `..` traversal path. When the developer later calls `agent.start(...)`, PraisonAI writes the agent response to that path with `open(..., "w")`, creating parent directories if needed.

This lets an untrusted project overwrite files outside the project root with the privileges of the user running PraisonAI.

## Technical Details

The source-to-sink path is `Agent.__init__()` project config loading to `OutputConfig.output_file` to public `agent.start()` output auto-save. `praisonaiagents/agent/agent.py` applies config-driven defaults before parameter resolution; if the caller did not explicitly pass `output`, it calls `apply_config_defaults("output", output, OutputConfig)`. `praisonaiagents/config/loader.py` treats a config block with `enabled = true` as active and instantiates `OutputConfig` from the remaining keys. `OutputConfig` includes `output_file`, and the agent stores that value as `self._output_file`.

After `agent.start(...)` obtains a truthy result from `self.chat(...)`, `praisonaiagents/agent/execution_mixin.py` calls `_save_output_to_file(str(result))` when `self._output_file` is set. `praisonaiagents/agent/memory_mixin.py` then runs `expanduser()` and `abspath()`, creates paren…