Venice vulnerable to Partial Path Traversal issue within the functions `load-file` and `load-resource`

Impact

A partial path traversal issue exists within the functions load-file and load-resource. These functions can be limited to load files from a list of load paths.

Assuming Venice has been configured with the load paths: [ "/Users/foo/resources" ]

When passing relative paths to these two vulnerable functions everything is fine: (load-resource "test.png") => loads the file "/Users/foo/resources/test.png" (load-resource "../resources-alt/test.png") => rejected, outside the load path

When passing absolute paths to these two vulnerable functions Venice may return files outside the configured load paths: (load-resource "/Users/foo/resources/test.png") => loads the file "/Users/foo/resources/test.png" (load-resource "/Users/foo/resources-alt/test.png") => loads the file "/Users/foo/resources-alt/test.png" !!! The latter call suffers from the Partial Path Traversal vulnerability.

This issue’s scope is limited to absolute paths whose name prefix matches a load path. E.g. for a load-path "/Users/foo/resources", the actor can cause loading a resource also from "/Users/foo/resources-alt", but not from "/Users/foo/images".

Versions of Venice before and including v1.10.16 are affected by this issue.

Patches

Upgrade to Venice >= 1.10.17, if you are on a version < 1.10.17

Workarounds

If you cannot upgrade the library, you can control the functions that can be used in Venice with a sandbox. If it is appropriate, the functions load-file and load-resource can be blacklisted in the sandbox.

References

• PR

For more information

If you have any questions or comments about this advisory:

• Open an issue in GitHub Venice
• Email us at juerg.ch

Credits

I want to publicly recognize the contribution of Jonathan Leitschuh for reporting this issue.