Ghost: Theme Upload Path Traversal

Impact

A vulnerability in custom themes allowed a staff user to write files outside of the uploads directory. This could be used to alter the behavior of the installation.

Vulnerable versions

This vulnerability is present in Ghost from v0.10.0 up to v6.54.0.

Patches

v6.54.1 contains a fix for this issue.

How to update

For self-hosters using Docker, find Docker's official Ghost image here. Updating a Docker-based Ghost instance is documented here.

If your Ghost is a Ghost-CLI install see our documentation on updating it to the latest version here.

References

Ghost thanks Stephen Sims, Off By One Security for disclosing this vulnerability responsibly.

For more information

If you have any questions or comments about this advisory, email Ghost at security@ghost.org.