GHSA-w2gf-jxc9-pf2q

### Summary Content in filesystem is accessible for reading using `sniff_csv`, even with `enable_external_access=false`. ### Details During a pentest, a security researcher was able to access environment variable data and other system data by using the `sniff_csv` function, even though we set `enable_external_access` to false. ### PoC ```SQL SET enable_external_access=false; SET lock_configuration=true; SELECT Columns FROM sniff_csv('/proc/self/environ'); ``` ### Impact Provides an attacker with access to filesystem even when access is expected to be disabled and other similar functions do NOT provide access. For example `select * from read_csv('/proc/self/environ')` fails with a permission error. There seems to be two vectors to this vulnerability: 1. Access to files that should otherwise not be allowed. (We expect `Permission Error: Scanning CSV files is disabled through configuration` and not to provide any access to the file or even acknowledge that it exists). 2. The content from a (non-csv?) file can be read (e.g. `/etc/hosts`, `proc/self/environ`, etc) even though that doesn't seem to be the intent of the sniff_csv function (my understanding is it's intending to provide information about the shape of the data, but not provide the data itself). ### Workaround It is possible to work around the issue by disabling the local file system using the `disabled_filesystems` setting: ```SQL SET disabled_filesystems='LocalFileSystem'; SET lock_configuration=true; SELECT Columns FROM sniff_csv('/proc/self/environ'); ``` will result in `Permission Error: File system LocalFileSystem has been disabled by configuration`. ### Fix A fix has been merged into the `main` branch (https://github.com/duckdb/duckdb/pull/13133), and will be released with the next DuckDB release.