CyberRota Analysis
AI-GeneratedZEBRA, a Zcash node implemented in Rust, is vulnerable to a denial-of-service attack where a malicious unauthenticated peer can exploit the block download process, causing significant synchronization delays for honest peers. This vulnerability can lead to repeated disruptions in the network's ability to sync, impacting overall performance without compromising data integrity. Users operating versions prior to 4.5.0 should prioritize upgrading to mitigate the risk of prolonged synchronization issues.
Public Exploit Signal
A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.
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Original NVD Description
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 zebrad/src/components/sync/downloads.rs, BlockDownloadVerifyError::AboveLookaheadHeightLimit originally carried only the block height and hash, so handle_block_response could not attribute the failure to the advertising peer. The error then reached the restart-worthy default path in zebrad/src/components/sync.rs, cancelling all in-flight downloads from honest peers and imposing a 67-second sync restart delay on mainnet. Because the peer was neither scored nor disconnected, the peer could repeat the cycle indefinitely with minimal bandwidth and significantly degrade synchronization without corrupting state. This issue is fixed in version 4.5.0.