CVE-2026-44498: Zfnd Zebrad

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

ZEBRA is a Zcash node written entirely in Rust. Prior to version 4.4.0, Zebra's block validator undercounts transparent signature operations against the 20000-sigop block limit (MAX_BLOCK_SIGOPS), allowing it to accept blocks that zcashd rejects with bad-blk-sigops. A miner who produces such a block can split the network: Zebra nodes follow the offending chain while zcashd nodes do not. This issue has been patched in version 4.4.0.

Affected products

• Zfnd Zebrad: before 4.4.0 (fixed in 4.4.0)

Published 2026-05-08. Last modified 2026-06-17.