Zcash Foundation Releases Zebra 4.4.0 on May 2, Fixing Multiple Consensus-Level Security Vulnerabilities

According to Zcash Foundation, Zebra 4.4.0 was released on May 2 to fix multiple consensus-level security vulnerabilities and strongly recommends all node operators upgrade immediately. The update addresses denial-of-service flaws that could halt new block discovery, block signature operation (sigops) counting errors causing consensus divergence, transparent transaction signature hash handling anomalies, and memory allocation amplification attack risks.

The foundation warned that some vulnerabilities could cause Zebra nodes to accept blocks rejected by zcashd, potentially triggering chain forks. Without timely updates, nodes face risks including block discovery interruption, consensus splits, and resource exhaustion, with no alternative mitigation currently available.