Malicious peer can make node stuck in blocksync in github.com/cometbft/cometbft

CometBFT is a distributed, Byzantine fault-tolerant, deterministic state machine replication engine. In the `blocksync` protocol peers send their `base` and `latest` heights when they connect to a new node (`A`), which is syncing to the tip of a network. `base` acts as a lower ground and informs `A` that the peer only has blocks starting from height `base`. `latest` height informs `A` about the latest block in a network. Normally, nodes would only report increasing heights. If `B` fails to provide the latest block, `B` is removed and the `latest` height (target height) is recalculated based on other nodes `latest` heights. The existing code however doesn't check for the case where `B` first reports `latest` height `X` and immediately after height `Y`, where `X > Y`. `A` will be trying to catch up to 2000 indefinitely. This condition requires the introduction of malicious code in the full node first reporting some non-existing `latest` height, then reporting lower `latest` height and nodes which are syncing using `blocksync` protocol. This issue has been patched in versions 1.0.1 and 0.38.17 and all users are advised to upgrade. Operators may attempt to ban malicious peers from the network as a workaround.

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对异常条件检查或处理不恰当

CometBFT 安全漏洞

CometBFT是CometBFT开源的一种拜占庭容错 (BFT) 中间件，它采用状态转换机（用任何编程语言编写）并可在许多机器上安全地复制。 CometBFT存在安全漏洞，该漏洞源于blocksync协议中未检查节点报告的latest高度递减的情况，导致同步节点无限期尝试追赶非存在的区块高度。

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