[Zcash Foundation Releases Zebra 4.4.0 to Fix Critical Vulnerabilities] According to the official announcement from the Zcash Foundation, Zebra version 4.4.0 has been released, addressing multiple consensus-level security vulnerabilities, including denial-of-service vulnerabilities, block signature operation miscount errors, abnormal handling of transparent transaction signature hashes, and risks of memory allocation amplification attacks. The foundation strongly recommends that node operators upgrade immediately to avoid issues such as block discovery interruptions, consensus forks, and amplified resource consumption caused by these vulnerabilities. Currently, there are no alternative mitigation solutions available.