Crayfish allows Remote Code Execution via Homarus Authorization header

Impact

Remote code execution may be possible in web-accessible installations of Homarus in certain configurations.

Patches

The issue has been patched in islandora/crayfish:4.1.0

Workarounds

The exploit requires making a request against the Homarus's /convert endpoint; therefore, the ability to exploit is much reduced if the microservice is not directly accessible from the Internet, so: Prevent general access from the Internet from hitting Homarus.

Configure auth in Crayfish to be more strongly required, such that requests with Authorization headers that do not validate are rejected before the problematic CLI interpolation occurs.

References

• XBOW-024-071