CVE-2022-45196: 
Python vulnerability analysis and mitigation

Hyperledger Fabric 2.3 contains a denial of service vulnerability (CVE-2022-45196) that allows attackers to cause an orderer crash by repeatedly sending a crafted channel tx with the same Channel name. The vulnerability was discovered in November 2022. The official Fabric with Raft implementation includes mitigations through a locking mechanism and checks for existing channel names (Fabric Issue, NVD).

The vulnerability exists in the orderer's multichannel registrar component. When processing channel creation transactions, the code would panic directly upon encountering errors related to WAL (Write-Ahead Logging) file locking. This occurs specifically in the CreateChain function where improper error handling allows an attacker to trigger a crash by exploiting race conditions around channel creation (Fabric Issue). The vulnerability has been assigned a CVSS v3.1 base score of 7.5 (High) with vector: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (NVD).

A successful exploitation of this vulnerability results in a denial of service condition where the orderer crashes and cannot be recovered. This affects the availability of the Hyperledger Fabric network as orderer nodes are critical components responsible for transaction ordering and block creation (NVD).

The vulnerability has been patched in later versions of Hyperledger Fabric. The official Fabric with Raft implementation includes mitigations through a locking mechanism and checks for existing channel names. Organizations running Fabric 2.3 should upgrade to a patched version. A fix was implemented that prevents creating a new chain if it already exists in the map of chains (Fabric PR).