Unsafe deserialisation in the PKI implementation scheme of NVFlare

Impact

NVFLARE contains a vulnerability in its PKI implementation module, where The CA credentials are transported via pickle and no safe deserialization. The deserialization of Untrusted Data may allow an unprivileged network attacker to cause Remote Code Execution, Denial Of Service, and Impact to both Confidentiality and Integrity.
All versions before 2.1.2 are affected.

CVSS Score = 9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Patches

The patch will be included in nvflare==2.1.2

Workarounds

Replace pickle serialization with JSON and change the code accordingly

Additional information
Issue Found by: Oliver Sellwood (@Nintorac)