Bitcoin Core developers disclosed three vulnerabilities that had already been fixed in versions 30.0 and 29.2, released on October 10 and October 14, 2025. One flaw could leave a mining node’s mempool inconsistent after a blockchain reorganization, preventing it from producing valid block templates until the software was restarted.
A second flaw could let a malicious peer delay compact-block processing by up to 10 minutes. The attack could be repeated without limit against nodes started with the -blocksonly parameter, or if the attacker controlled all three of a node’s high-bandwidth peers. A third flaw could give Tor connections privileged access and weaken denial-of-service protections and privacy, but only under a non-standard whitelist configuration; nodes without it were not vulnerable to that issue.
