CVE-2026-52737

Zebra (v4.4.1 and earlier) is vulnerable to a DoS: a malicious unauthenticated P2P peer serves a block with an above-lookahead coinbase height, triggering a 67-second global sync restart that cancels honest peer downloads indefinitely. The root cause is that BlockDownloadVerifyError::AboveLookahe...

CVE-2026-52737 ZEBRA: Sync restart poisoning from single unauthenticated peer via above-lookahead block

ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, a malicious unauthenticated P2P peer can answer Zebra's outbound getblocks or FindBlocks request with a small two-hash inventory and then serve a syntactically valid block whose coinbase height is far above the local chain tip. In...

GHSA-GVJC-3W7C-92JX Zebra has sync restart poisoning from single unauthenticated peer via above-lookahead block

Am I affected You are affected if: 1. You run zebrad up to and including v4.4.1. 2. Your node accepts inbound P2P connections and is syncing or catching up to the chain tip. Summary A malicious peer can answer Zebra's outbound getblocks/FindBlocks request with a small two-hash inventory, then ser...

PT-2026-55473

Name of the Vulnerable Software and Affected Versions ZEBRA versions prior to 4.4.2 Description A malicious unauthenticated P2P peer can degrade the synchronization of a Zcash node by responding to outbound getblocks or FindBlocks requests with a small two-hash inventory and a syntactically valid...